🕷️ Crawler Inspector

URL Lookup

Direct Parameter Lookup

Raw Queries and Responses

1. Shard Calculation

Query:

Response:

Calculated Shard: 72 (from laksa090)

2. Crawled Status Check

Query:

curl -X POST \
  'http://laksa072.int.ahrefs:8124/' \
  -H 'Content-Type: text/plain' \
  -H 'X-ClickHouse-Database: crawler3' \
  -H 'Authorization: Basic YXBpOg==' \
  -d 'SELECT getAhrefsURLFromUnparsed(src_unparsed) AS found_url, ifNull(toUnixTimestamp(download_stamp), 0) AS crawl_time, ifNull(toUnixTimestamp(props_url_first_seen), 0) AS first_indexed_time, download_http_code AS http_code, src_unparsed AS src_unparsed, src_root_hash AS src_root_hash, history_drop_reason AS history_drop_reason, meta_title AS meta_title, meta_descriptions AS meta_descriptions, attrs_boilerpipe_text AS attrs_boilerpipe_text, attrs_markdown AS attrs_markdown, attrs_readable_markdown AS attrs_readable_markdown, meta_canonical AS meta_canonical FROM crawler3.page_info_local FINAL PREWHERE (src_root_hash, src_unparsed) IN ((getAhrefsRootHashFromUnparsed(getAhrefsUnparsedNoserviceFromURL(\'https://optionalpha.com/learn/bollinger-bands\')), getAhrefsUnparsedNoserviceFromURL(\'https://optionalpha.com/learn/bollinger-bands\'))) FORMAT JSONEachRow'

Response:

{"found_url":"https:\/\/optionalpha.com\/learn\/bollinger-bands","crawl_time":1775083229,"first_indexed_time":1684194643,"http_code":200,"src_unparsed":"com,optionalpha!\/learn\/bollinger-bands s443","src_root_hash":"6261014955454694472","history_drop_reason":null,"meta_title":"Bollinger Bands: What They Are & How to Use Them","meta_descriptions":["Bollinger bands are a volatility technical indicator that show the upper and lower range of normal price movement using standard deviation."],"attrs_boilerpipe_text":"Bollinger Bands are a volatility indicator created by\nJohn Bollinger\n. Bollinger Bands consist of a\nsimple moving average (SMA)\nand two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two\nstandard deviations\n.\nThe bands are dynamic and display changes in volatility. They widen when price volatility is increasing and contract when volatility decreases, allowing traders to quickly identify periods of high and low volatility.\nBollinger Bands provide a relative definition of high and low prices for a given ticker symbol. By definition, prices are considered high at the upper band and low at the lower band. Traders can use this information to determine whether prices are relatively high or low in comparison to past price action.\nIf the bands are drawn two standard deviations above and below the center simple moving average, approximately 95% of the security’s price action should occur within the bands.\nPrice moving above the upper band or below the lower band is often used as trading signal. Price tends to oscillate within the bands, so the upper and lower bands can be used as resistance and support or as a breakout signal.\nWhen combined with other\ntechnical indicators\n, such as\nMACD\nand\nRSI\n, Bollinger Bands can help identify overbought\/oversold conditions, trend reversals, continuation, and more.\nBollinger bands are used to measure volatility and define potential price channels or\ntrends\n. When prices move outside the bands, it can indicate that a new trend is beginning or that prices have become overextended.\nThere are many Bollinger Bands strategies and traders use the indicator several ways.\nMean reversion\ntraders may buy the security when its price touches the lower band and sell when price hits the upper band. Conversely,\nmomentum traders\ncould use the bands as a signal that price will continue and buy near the upper band or sell near the lower band.\nCalculating Bollinger Bands\nBollinger Bands consist of three lines. The middle line is a simple moving average (SMA) and the upper and lower lines are ‘n’ standard deviations above and below the SMA, respectively. Calculating Bollinger Bands is fairly straightforward:\nCalculate a simple moving average of the asset’s price over a specific time period.\nCalculate standard deviation over the same time period.\nDraw lines 'n' standard deviation above and below the SMA to get the upper and lower bands.\nFAQs\nWhat are Bollinger Bands?\nBollinger Bands are a volatility indicator created by\nJohn Bollinger\n. Bollinger Bands consist of a\nsimple moving average (SMA)\nand two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two\nstandard deviations\n.\nHow to read Bollinger Bands?\nThe main purpose of Bollinger Bands is to provide traders with a relative definition of high and low prices for a given market. By definition, prices are high at the upper band and low at the lower band. This information can be used to determine whether prices are relatively high or low in comparison to past price action.\nPrice tends to oscillate within the bands and the upper and lower bands can be used as resistance and support. Breakouts above the upper band or below the lower band are often used as trading signals.\nHow do you use Bollinger bands?\nBollinger bands are used to measure price volatility. When the bands widen, price volatility is increasing and when the bands contract, volatility is decreasing.\nYou can use Bollinger Bands to identify price action that is overextended.\nMean reversion\nand\ntrend following\ntraders use Bollinger Bands to go long or short a security based on their interpretation of the trading signal.\nHow Accurate are Bollinger Bands?\nBollinger Bands are a reliable and effective tool for measuring market volatility. They provide traders with an objective measure of whether prices are high or low on a relative basis.\nBollinger Bands are a lagging indicator but they're a popular tool due to their simplicity and effectiveness in gauging market volatility. Traders can combine them with other\ntechnical indicators\nto predict future price movements.","attrs_markdown":"Get Option Alpha **100% FREE** by connecting your TradeStation or Tradier brokerage account! [Learn more](https:\/\/optionalpha.com\/pricing).\n\n📣 75% OFF Early Bird Sale\\!\n\nSpecial Easter Pricing this week only 👉 [Learn more](https:\/\/optionalpha.com\/new-year).\n\n📣 72% OFF Sale\\!\n\nEnds tonight at midnight! 👉 [Learn more](https:\/\/optionalpha.com\/new-year).\n\n[![Option Alpha logo](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/62388f2777982d6b8344216a_oa%20logo.svg)](https:\/\/optionalpha.com\/)\n\n[Home](https:\/\/optionalpha.com\/)\n\n[Resources](https:\/\/optionalpha.com\/resources)![](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/5fba23eb8789c3e735fb5f5b_icon-chevron-down.svg)\n\n[Bots 101](https:\/\/optionalpha.com\/bots-101)[Integrations](https:\/\/optionalpha.com\/integrations)\n\n[Education](https:\/\/optionalpha.com\/education)![](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/5fba23eb8789c3e735fb5f5b_icon-chevron-down.svg)\n\n[Courses](https:\/\/optionalpha.com\/courses)[Strategies](https:\/\/optionalpha.com\/options-strategies)[Handbook](https:\/\/optionalpha.com\/handbook)[Podcast](https:\/\/optionalpha.com\/podcast)[Blog](https:\/\/optionalpha.com\/blog)\n\n[Pricing](https:\/\/optionalpha.com\/pricing)[Brokers](https:\/\/optionalpha.com\/integrations)[FAQ](https:\/\/optionalpha.com\/faqs)\n\n[Cyber Monday](https:\/\/optionalpha.com\/black-friday)\n\n[SAVE 72%](https:\/\/optionalpha.com\/black-friday)\n\n[Start Free Trial](https:\/\/optionalpha.com\/start)[Login](https:\/\/app.optionalpha.com\/login)\n\n[](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\n[Login](https:\/\/app.optionalpha.com\/login)[Start Free Trial](https:\/\/optionalpha.com\/start)\n\n![mobile nav menu](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/5fba23eb8789c37f75fb5f67_icon-menu.svg)\n\n[Home](https:\/\/optionalpha.com\/)\n\n[Education](https:\/\/optionalpha.com\/education)\n\n[Handbook](https:\/\/optionalpha.com\/handbook)\n\n[Technical Indicators](https:\/\/optionalpha.com\/topics\/technical-indicators)\n\n[Bollinger Bands](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\n# Bollinger Bands\nBollinger bands are a volatility technical indicator that show the upper and lower range of normal price movement using standard deviation.\n\n[View risk disclosures](https:\/\/optionalpha.com\/legal\/risk-disclosure-agreement)\n\n[optionalpha.com\/learn\/bollinger-bands](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\nBollinger Bands are a volatility indicator created by [John Bollinger](https:\/\/www.bollingerbands.com\/). Bollinger Bands consist of a [simple moving average (SMA)](https:\/\/optionalpha.com\/learn\/simple-moving-average) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two [standard deviations](https:\/\/optionalpha.com\/topics\/financial-modeling).\n\nThe bands are dynamic and display changes in volatility. They widen when price volatility is increasing and contract when volatility decreases, allowing traders to quickly identify periods of high and low volatility.\n\n![Bollinger Bands](https:\/\/cdn.prod.website-files.com\/5fba23eb8789c3c7fcfb5f31\/64627b34b8470bc52cbb54ab_Bollinger%20Bands.jpeg)\n\nBollinger Bands provide a relative definition of high and low prices for a given ticker symbol. By definition, prices are considered high at the upper band and low at the lower band. Traders can use this information to determine whether prices are relatively high or low in comparison to past price action.\n\nIf the bands are drawn two standard deviations above and below the center simple moving average, approximately 95% of the security’s price action should occur within the bands.\n\n![Standard Deviation](https:\/\/cdn.prod.website-files.com\/5fba23eb8789c3c7fcfb5f31\/64627b4eb8470bc52cbb6dc4_StandardDeviation.png)\n\nPrice moving above the upper band or below the lower band is often used as trading signal. Price tends to oscillate within the bands, so the upper and lower bands can be used as resistance and support or as a breakout signal.\n\nWhen combined with other [technical indicators](https:\/\/optionalpha.com\/topics\/technical-indicators), such as [MACD](https:\/\/optionalpha.com\/learn\/macd-indicator) and [RSI](https:\/\/optionalpha.com\/learn\/rsi-indicator), Bollinger Bands can help identify overbought\/oversold conditions, trend reversals, continuation, and more.\n\n## **How to Use Bollinger Bands**\nBollinger bands are used to measure volatility and define potential price channels or [trends](https:\/\/optionalpha.com\/topics\/trend-trading). When prices move outside the bands, it can indicate that a new trend is beginning or that prices have become overextended.\n\nThere are many Bollinger Bands strategies and traders use the indicator several ways. [Mean reversion](https:\/\/optionalpha.com\/learn\/mean-reversion) traders may buy the security when its price touches the lower band and sell when price hits the upper band. Conversely, [momentum traders](https:\/\/optionalpha.com\/topics\/momentum-trading) could use the bands as a signal that price will continue and buy near the upper band or sell near the lower band.\n\n## **Calculating Bollinger Bands**\nBollinger Bands consist of three lines. The middle line is a simple moving average (SMA) and the upper and lower lines are ‘n’ standard deviations above and below the SMA, respectively. Calculating Bollinger Bands is fairly straightforward:\n\n- Calculate a simple moving average of the asset’s price over a specific time period.\n- Calculate standard deviation over the same time period.\n- Draw lines 'n' standard deviation above and below the SMA to get the upper and lower bands.\n\n## FAQs\n### What are Bollinger Bands?\nBollinger Bands are a volatility indicator created by [John Bollinger](https:\/\/www.bollingerbands.com\/). Bollinger Bands consist of a [simple moving average (SMA)](https:\/\/optionalpha.com\/learn\/simple-moving-average) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two [standard deviations](https:\/\/optionalpha.com\/topics\/financial-modeling).\n\n### How to read Bollinger Bands?\nThe main purpose of Bollinger Bands is to provide traders with a relative definition of high and low prices for a given market. By definition, prices are high at the upper band and low at the lower band. This information can be used to determine whether prices are relatively high or low in comparison to past price action.\n\nPrice tends to oscillate within the bands and the upper and lower bands can be used as resistance and support. Breakouts above the upper band or below the lower band are often used as trading signals.\n\n### How do you use Bollinger bands?\nBollinger bands are used to measure price volatility. When the bands widen, price volatility is increasing and when the bands contract, volatility is decreasing.\n\nYou can use Bollinger Bands to identify price action that is overextended. [Mean reversion](https:\/\/optionalpha.com\/learn\/mean-reversion) and [trend following](https:\/\/optionalpha.com\/topics\/trend-trading) traders use Bollinger Bands to go long or short a security based on their interpretation of the trading signal.\n\n### How Accurate are Bollinger Bands?\nBollinger Bands are a reliable and effective tool for measuring market volatility. They provide traders with an objective measure of whether prices are high or low on a relative basis.\n\nBollinger Bands are a lagging indicator but they're a popular tool due to their simplicity and effectiveness in gauging market volatility. Traders can combine them with other [technical indicators](https:\/\/optionalpha.com\/topics\/technical-indicators) to predict future price movements.\n\nContributors\n\n[![Steve Henry](https:\/\/cdn.prod.website-files.com\/5fba23eb8789c3c7fcfb5f31\/607d8edd49b20c84ee842820_Steve-Henry-Avatar.png)Steve Henry Content Director](https:\/\/optionalpha.com\/team\/steve-henry)\n\n[![Kirk Du Plessis](https:\/\/cdn.prod.website-files.com\/5fba23eb8789c3c7fcfb5f31\/622fa2005a5fabed64659616_607d8ea5221240c8618ea3d1_Kirk-Du-Plessis-Avatar%20\\(1\\).png)Kirk Du Plessis Founder](https:\/\/optionalpha.com\/team\/kirk-duplessis)\n\nLast updated:\n\nMay 15, 2023\n\nSep 13, 2023\n\nOriginally published:\n\nMay 15, 2023\n\n[Technical Indicators](https:\/\/optionalpha.com\/tags\/technical-indicators)\n\n[Technical Analysis](https:\/\/optionalpha.com\/tags\/technical-analysis)\n\n[SMA](https:\/\/optionalpha.com\/tags\/sma)\n\n[Volatility](https:\/\/optionalpha.com\/tags\/volatility)\n\nHighlights\n\n- Bollinger Bands measure a security's price volatility.\n- Bollinger Bands use a simple moving average and standard deviation.\n- Traders use Bollinger Bands as a trend following or mean reversion trading signal.\n\nOn this page\n\n[Example H2](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\n[Example H3](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\n[Example H4](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\n[FAQs](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\nPopular...\n\n[![](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/641de0644de07e3f3767b593_CleanShot%202023-03-24%20at%2013.20.01%402x.png)GuidesAutotrading Quick-StartThis 4-part guide shows you how to safely get started with automated trading by the end of the day.](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\n[Watch Now](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\n![](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/672928e7bf3c2c6cda7cd914_Trade%20with%20conviction.png)\n\nTrade with conviction\n\nFind an edge backtesting 0DTE and next day strategies using 1 minute data then leverage automation to execute your strategy better than humanly possible.\n\n[Start My Free Trial](https:\/\/optionalpha.com\/start)\n\n## You might also like\nOur philosophy is simple — publish options education that's better than everyone else. No ads, no fluff, no subjective bias; just the facts beautifully organized for you.\n\n[![](https:\/\/cdn.prod.website-files.com\/5fba23eb8789c3c7fcfb5f31\/630f3030c0454ef8b770b05f_file-05.svg) Learn how to automate a Bollinger Band strategy This blog shows you how to build a bot using debit and credit spreads to trade breakouts.Read more](https:\/\/optionalpha.com\/blog\/how-to-automate-a-bollinger-band-strategy)\n\n[![](https:\/\/cdn.prod.website-files.com\/5fba23eb8789c3c7fcfb5f31\/630f2f929fdc655f4b40d7a2_book-open-01.svg) Here's your complete guide to trading option spreads This page has everything you need to know about short put spreads and short call spreadsRead more](https:\/\/optionalpha.com\/learn\/vertical-spread)\n\n###### Trade with discipline and consistency\n**Find opportunities. Backtest ideas. Automate strategies.**\n\n[Learn more](https:\/\/optionalpha.com\/backtester-start)\n\n[Start Free Trial](https:\/\/optionalpha.com\/start)\n\n![MacBook mockup](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/69bf495868c38bcbe09ef10e_tradeideas.png)\n\n[![Option Alpha logo](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/635030ca6aea371383d0ef5b_oa%20logo%203x%20-%20white.png)](https:\/\/optionalpha.com\/)\n\n- [![Facebook Icon](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/5fba23eb8789c366fcfb5fb6_facebook.svg)](https:\/\/www.facebook.com\/OptionAlphaCompany)\n- [![Instagram Icon](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/5fba23eb8789c34ca5fb5f98_instagram.svg)](https:\/\/www.instagram.com\/optionalpha\/)\n- [![Youtube Icon](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/5fba23eb8789c3a9b3fb5f72_youtube.svg)](https:\/\/www.youtube.com\/OptionAlpha?sub_confirmation=1)\n- [![LinkedIn Icon](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/5fba23eb8789c37ad3fb5f74_linkedin.svg)](https:\/\/www.linkedin.com\/company\/optionalpha)\n- [![Twitter Icon](https:\/\/cdn.prod.website-files.com\/5fba23ebc651c6d16f446fc4\/5fba23eb8789c359d0fb5f7a_twitter.svg)](https:\/\/twitter.com\/OptionAlpha)\n\n###### Platform\n- [Bots](https:\/\/optionalpha.com\/bots)\n- [Templates](https:\/\/optionalpha.com\/templates)\n- [Integrations](https:\/\/optionalpha.com\/integrations)\n- [Backtester](https:\/\/optionalpha.com\/backtester)\n- [Community](https:\/\/optionalpha.com\/community)\n\n###### Resources\n- [Bots 101](https:\/\/optionalpha.com\/bots-101)\n- [Workshops](https:\/\/app.livestorm.co\/optionalpha)\n- [Videos](https:\/\/optionalpha.com\/videos)\n\n###### Education\n- [Courses](https:\/\/optionalpha.com\/courses)\n- [Strategies](https:\/\/optionalpha.com\/options-strategies)\n- [Handbook](https:\/\/optionalpha.com\/handbook)\n- [Podcast](https:\/\/optionalpha.com\/podcast)\n- [Blog](https:\/\/optionalpha.com\/blog)\n\n###### Company\n- [About](https:\/\/optionalpha.com\/about-us)\n- [Careers](https:\/\/optionalpha.com\/careers)\n- [Team](https:\/\/optionalpha.com\/team)\n- [Legal](https:\/\/optionalpha.com\/legal)\n- [Help](https:\/\/docs.optionalpha.com\/)\n- [Contact](https:\/\/optionalpha.com\/contact)\n- [Status](https:\/\/status.optionalpha.com\/)\n\n© 2026 Option Alpha. All Rights Reserved. Patent Pending USSN 63\/118,547\n\n[![California Consumer Privacy Act (CCPA) Opt-Out Icon](<data:image\/svg+xml;charset=UTF-8,%3csvg version='1.1' id='Layer_1' xmlns='http:\/\/www.w3.org\/2000\/svg' xmlns:xlink='http:\/\/www.w3.org\/1999\/xlink' x='0px' y='0px' viewBox='0 0 30 14' style='enable-background:new 0 0 30 14;' xml:space='preserve'%3e%3cstyle type='text\/css'%3e .st0%7bfill-rule:evenodd;clip-rule:evenodd;fill:%23FFFFFF;%7d .st1%7bfill-rule:evenodd;clip-rule:evenodd;fill:%230066FF;%7d .st2%7bfill:%23FFFFFF;%7d .st3%7bfill:%230066FF;%7d %3c\/style%3e%3cg%3e%3cg id='final---dec.11-2020_1_'%3e%3cg id='_x30_208-our-toggle_2_' transform='translate(-1275.000000, -200.000000)'%3e%3cg id='Final-Copy-2_2_' transform='translate(1275.000000, 200.000000)'%3e%3cpath class='st0' d='M7.4,12.8h6.8l3.1-11.6H7.4C4.2,1.2,1.6,3.8,1.6,7S4.2,12.8,7.4,12.8z'\/%3e%3c\/g%3e%3c\/g%3e%3c\/g%3e%3cg id='final---dec.11-2020'%3e%3cg id='_x30_208-our-toggle' transform='translate(-1275.000000, -200.000000)'%3e%3cg id='Final-Copy-2' transform='translate(1275.000000, 200.000000)'%3e%3cpath class='st1' d='M22.6,0H7.4c-3.9,0-7,3.1-7,7s3.1,7,7,7h15.2c3.9,0,7-3.1,7-7S26.4,0,22.6,0z M1.6,7c0-3.2,2.6-5.8,5.8-5.8 h9.9l-3.1,11.6H7.4C4.2,12.8,1.6,10.2,1.6,7z'\/%3e%3cpath id='x' class='st2' d='M24.6,4c0.2,0.2,0.2,0.6,0,0.8l0,0L22.5,7l2.2,2.2c0.2,0.2,0.2,0.6,0,0.8c-0.2,0.2-0.6,0.2-0.8,0 l0,0l-2.2-2.2L19.5,10c-0.2,0.2-0.6,0.2-0.8,0c-0.2-0.2-0.2-0.6,0-0.8l0,0L20.8,7l-2.2-2.2c-0.2-0.2-0.2-0.6,0-0.8 c0.2-0.2,0.6-0.2,0.8,0l0,0l2.2,2.2L23.8,4C24,3.8,24.4,3.8,24.6,4z'\/%3e%3cpath id='y' class='st3' d='M12.7,4.1c0.2,0.2,0.3,0.6,0.1,0.8l0,0L8.6,9.8C8.5,9.9,8.4,10,8.3,10c-0.2,0.1-0.5,0.1-0.7-0.1l0,0 L5.4,7.7c-0.2-0.2-0.2-0.6,0-0.8c0.2-0.2,0.6-0.2,0.8,0l0,0L8,8.6l3.8-4.5C12,3.9,12.4,3.9,12.7,4.1z'\/%3e%3c\/g%3e%3c\/g%3e%3c\/g%3e%3c\/g%3e%3c\/svg%3e>) Your Privacy Choices](https:\/\/optionalpha.com\/learn\/bollinger-bands)\n\n[Notice at Collection](https:\/\/optionalpha.com\/learn\/bollinger-bands)","attrs_readable_markdown":"Bollinger Bands are a volatility indicator created by [John Bollinger](https:\/\/www.bollingerbands.com\/). Bollinger Bands consist of a [simple moving average (SMA)](https:\/\/optionalpha.com\/learn\/simple-moving-average) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two [standard deviations](https:\/\/optionalpha.com\/topics\/financial-modeling).\n\nThe bands are dynamic and display changes in volatility. They widen when price volatility is increasing and contract when volatility decreases, allowing traders to quickly identify periods of high and low volatility.\n\n![Bollinger Bands](https:\/\/cdn.prod.website-files.com\/5fba23eb8789c3c7fcfb5f31\/64627b34b8470bc52cbb54ab_Bollinger%20Bands.jpeg)\n\nBollinger Bands provide a relative definition of high and low prices for a given ticker symbol. By definition, prices are considered high at the upper band and low at the lower band. Traders can use this information to determine whether prices are relatively high or low in comparison to past price action.\n\nIf the bands are drawn two standard deviations above and below the center simple moving average, approximately 95% of the security’s price action should occur within the bands.\n\n![Standard Deviation](https:\/\/cdn.prod.website-files.com\/5fba23eb8789c3c7fcfb5f31\/64627b4eb8470bc52cbb6dc4_StandardDeviation.png)\n\nPrice moving above the upper band or below the lower band is often used as trading signal. Price tends to oscillate within the bands, so the upper and lower bands can be used as resistance and support or as a breakout signal.\n\nWhen combined with other [technical indicators](https:\/\/optionalpha.com\/topics\/technical-indicators), such as [MACD](https:\/\/optionalpha.com\/learn\/macd-indicator) and [RSI](https:\/\/optionalpha.com\/learn\/rsi-indicator), Bollinger Bands can help identify overbought\/oversold conditions, trend reversals, continuation, and more.\n\nBollinger bands are used to measure volatility and define potential price channels or [trends](https:\/\/optionalpha.com\/topics\/trend-trading). When prices move outside the bands, it can indicate that a new trend is beginning or that prices have become overextended.\n\nThere are many Bollinger Bands strategies and traders use the indicator several ways. [Mean reversion](https:\/\/optionalpha.com\/learn\/mean-reversion) traders may buy the security when its price touches the lower band and sell when price hits the upper band. Conversely, [momentum traders](https:\/\/optionalpha.com\/topics\/momentum-trading) could use the bands as a signal that price will continue and buy near the upper band or sell near the lower band.\n\n## **Calculating Bollinger Bands**\nBollinger Bands consist of three lines. The middle line is a simple moving average (SMA) and the upper and lower lines are ‘n’ standard deviations above and below the SMA, respectively. Calculating Bollinger Bands is fairly straightforward:\n\n- Calculate a simple moving average of the asset’s price over a specific time period.\n- Calculate standard deviation over the same time period.\n- Draw lines 'n' standard deviation above and below the SMA to get the upper and lower bands.\n\nFAQs\n\n### What are Bollinger Bands?\nBollinger Bands are a volatility indicator created by [John Bollinger](https:\/\/www.bollingerbands.com\/). Bollinger Bands consist of a [simple moving average (SMA)](https:\/\/optionalpha.com\/learn\/simple-moving-average) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two [standard deviations](https:\/\/optionalpha.com\/topics\/financial-modeling).\n\n### How to read Bollinger Bands?\nThe main purpose of Bollinger Bands is to provide traders with a relative definition of high and low prices for a given market. By definition, prices are high at the upper band and low at the lower band. This information can be used to determine whether prices are relatively high or low in comparison to past price action.\n\nPrice tends to oscillate within the bands and the upper and lower bands can be used as resistance and support. Breakouts above the upper band or below the lower band are often used as trading signals.\n\n### How do you use Bollinger bands?\nBollinger bands are used to measure price volatility. When the bands widen, price volatility is increasing and when the bands contract, volatility is decreasing.\n\nYou can use Bollinger Bands to identify price action that is overextended. [Mean reversion](https:\/\/optionalpha.com\/learn\/mean-reversion) and [trend following](https:\/\/optionalpha.com\/topics\/trend-trading) traders use Bollinger Bands to go long or short a security based on their interpretation of the trading signal.\n\n### How Accurate are Bollinger Bands?\nBollinger Bands are a reliable and effective tool for measuring market volatility. They provide traders with an objective measure of whether prices are high or low on a relative basis.\n\nBollinger Bands are a lagging indicator but they're a popular tool due to their simplicity and effectiveness in gauging market volatility. Traders can combine them with other [technical indicators](https:\/\/optionalpha.com\/topics\/technical-indicators) to predict future price movements.","meta_canonical":null}

3. Robots.txt Check

Query:

Response:

4. Spam/Ban Check

Query:

Response:

5. Seen Status Check

ℹ️ Skipped - page is already crawled

📄

INDEXABLE

✅

CRAWLED

6 days ago

🤖

ROBOTS ALLOWED

Page Info Filters

Filter	Status	Condition	Details
HTTP status	PASS	`download_http_code = 200`	HTTP 200
Age cutoff	PASS	`download_stamp > now() - 6 MONTH`	0.2 months ago
History drop	PASS	`isNull(history_drop_reason)`	No drop reason
Spam/ban	PASS	`fh_dont_index != 1 AND ml_spam_score = 0`	ml_spam_score=0
Canonical	PASS	`meta_canonical IS NULL OR = '' OR = src_unparsed`	Not set

Page Details

Property	Value
URL	https://optionalpha.com/learn/bollinger-bands
Last Crawled	2026-04-01 22:40:29 (6 days ago)
First Indexed	2023-05-15 23:50:43 (2 years ago)
HTTP Status Code	200
Meta Title	Bollinger Bands: What They Are & How to Use Them
Meta Description	Bollinger bands are a volatility technical indicator that show the upper and lower range of normal price movement using standard deviation.
Meta Canonical	null
Boilerpipe Text	Bollinger Bands are a volatility indicator created by John Bollinger . Bollinger Bands consist of a simple moving average (SMA) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two standard deviations . The bands are dynamic and display changes in volatility. They widen when price volatility is increasing and contract when volatility decreases, allowing traders to quickly identify periods of high and low volatility. Bollinger Bands provide a relative definition of high and low prices for a given ticker symbol. By definition, prices are considered high at the upper band and low at the lower band. Traders can use this information to determine whether prices are relatively high or low in comparison to past price action. If the bands are drawn two standard deviations above and below the center simple moving average, approximately 95% of the security’s price action should occur within the bands. Price moving above the upper band or below the lower band is often used as trading signal. Price tends to oscillate within the bands, so the upper and lower bands can be used as resistance and support or as a breakout signal. When combined with other technical indicators , such as MACD and RSI , Bollinger Bands can help identify overbought/oversold conditions, trend reversals, continuation, and more. Bollinger bands are used to measure volatility and define potential price channels or trends . When prices move outside the bands, it can indicate that a new trend is beginning or that prices have become overextended. There are many Bollinger Bands strategies and traders use the indicator several ways. Mean reversion traders may buy the security when its price touches the lower band and sell when price hits the upper band. Conversely, momentum traders could use the bands as a signal that price will continue and buy near the upper band or sell near the lower band. Calculating Bollinger Bands Bollinger Bands consist of three lines. The middle line is a simple moving average (SMA) and the upper and lower lines are ‘n’ standard deviations above and below the SMA, respectively. Calculating Bollinger Bands is fairly straightforward: Calculate a simple moving average of the asset’s price over a specific time period. Calculate standard deviation over the same time period. Draw lines 'n' standard deviation above and below the SMA to get the upper and lower bands. FAQs What are Bollinger Bands? Bollinger Bands are a volatility indicator created by John Bollinger . Bollinger Bands consist of a simple moving average (SMA) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two standard deviations . How to read Bollinger Bands? The main purpose of Bollinger Bands is to provide traders with a relative definition of high and low prices for a given market. By definition, prices are high at the upper band and low at the lower band. This information can be used to determine whether prices are relatively high or low in comparison to past price action. Price tends to oscillate within the bands and the upper and lower bands can be used as resistance and support. Breakouts above the upper band or below the lower band are often used as trading signals. How do you use Bollinger bands? Bollinger bands are used to measure price volatility. When the bands widen, price volatility is increasing and when the bands contract, volatility is decreasing. You can use Bollinger Bands to identify price action that is overextended. Mean reversion and trend following traders use Bollinger Bands to go long or short a security based on their interpretation of the trading signal. How Accurate are Bollinger Bands? Bollinger Bands are a reliable and effective tool for measuring market volatility. They provide traders with an objective measure of whether prices are high or low on a relative basis. Bollinger Bands are a lagging indicator but they're a popular tool due to their simplicity and effectiveness in gauging market volatility. Traders can combine them with other technical indicators to predict future price movements.
Markdown	Get Option Alpha 100% FREE by connecting your TradeStation or Tradier brokerage account! [Learn more](https://optionalpha.com/pricing). 📣 75% OFF Early Bird Sale\! Special Easter Pricing this week only 👉 [Learn more](https://optionalpha.com/new-year). 📣 72% OFF Sale\! Ends tonight at midnight! 👉 [Learn more](https://optionalpha.com/new-year). [![Option Alpha logo](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/62388f2777982d6b8344216a_oa%20logo.svg)](https://optionalpha.com/) [Home](https://optionalpha.com/) [Resources](https://optionalpha.com/resources)![](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/5fba23eb8789c3e735fb5f5b_icon-chevron-down.svg) [Bots 101](https://optionalpha.com/bots-101)[Integrations](https://optionalpha.com/integrations) [Education](https://optionalpha.com/education)![](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/5fba23eb8789c3e735fb5f5b_icon-chevron-down.svg) [Courses](https://optionalpha.com/courses)[Strategies](https://optionalpha.com/options-strategies)[Handbook](https://optionalpha.com/handbook)[Podcast](https://optionalpha.com/podcast)[Blog](https://optionalpha.com/blog) [Pricing](https://optionalpha.com/pricing)[Brokers](https://optionalpha.com/integrations)[FAQ](https://optionalpha.com/faqs) [Cyber Monday](https://optionalpha.com/black-friday) [SAVE 72%](https://optionalpha.com/black-friday) [Start Free Trial](https://optionalpha.com/start)[Login](https://app.optionalpha.com/login) [](https://optionalpha.com/learn/bollinger-bands) [Login](https://app.optionalpha.com/login)[Start Free Trial](https://optionalpha.com/start) ![mobile nav menu](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/5fba23eb8789c37f75fb5f67_icon-menu.svg) [Home](https://optionalpha.com/) [Education](https://optionalpha.com/education) [Handbook](https://optionalpha.com/handbook) [Technical Indicators](https://optionalpha.com/topics/technical-indicators) [Bollinger Bands](https://optionalpha.com/learn/bollinger-bands) # Bollinger Bands Bollinger bands are a volatility technical indicator that show the upper and lower range of normal price movement using standard deviation. [View risk disclosures](https://optionalpha.com/legal/risk-disclosure-agreement) [optionalpha.com/learn/bollinger-bands](https://optionalpha.com/learn/bollinger-bands) Bollinger Bands are a volatility indicator created by [John Bollinger](https://www.bollingerbands.com/). Bollinger Bands consist of a [simple moving average (SMA)](https://optionalpha.com/learn/simple-moving-average) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two [standard deviations](https://optionalpha.com/topics/financial-modeling). The bands are dynamic and display changes in volatility. They widen when price volatility is increasing and contract when volatility decreases, allowing traders to quickly identify periods of high and low volatility. ![Bollinger Bands](https://cdn.prod.website-files.com/5fba23eb8789c3c7fcfb5f31/64627b34b8470bc52cbb54ab_Bollinger%20Bands.jpeg) Bollinger Bands provide a relative definition of high and low prices for a given ticker symbol. By definition, prices are considered high at the upper band and low at the lower band. Traders can use this information to determine whether prices are relatively high or low in comparison to past price action. If the bands are drawn two standard deviations above and below the center simple moving average, approximately 95% of the security’s price action should occur within the bands. ![Standard Deviation](https://cdn.prod.website-files.com/5fba23eb8789c3c7fcfb5f31/64627b4eb8470bc52cbb6dc4_StandardDeviation.png) Price moving above the upper band or below the lower band is often used as trading signal. Price tends to oscillate within the bands, so the upper and lower bands can be used as resistance and support or as a breakout signal. When combined with other [technical indicators](https://optionalpha.com/topics/technical-indicators), such as [MACD](https://optionalpha.com/learn/macd-indicator) and [RSI](https://optionalpha.com/learn/rsi-indicator), Bollinger Bands can help identify overbought/oversold conditions, trend reversals, continuation, and more. ## How to Use Bollinger Bands Bollinger bands are used to measure volatility and define potential price channels or [trends](https://optionalpha.com/topics/trend-trading). When prices move outside the bands, it can indicate that a new trend is beginning or that prices have become overextended. There are many Bollinger Bands strategies and traders use the indicator several ways. [Mean reversion](https://optionalpha.com/learn/mean-reversion) traders may buy the security when its price touches the lower band and sell when price hits the upper band. Conversely, [momentum traders](https://optionalpha.com/topics/momentum-trading) could use the bands as a signal that price will continue and buy near the upper band or sell near the lower band. ## Calculating Bollinger Bands Bollinger Bands consist of three lines. The middle line is a simple moving average (SMA) and the upper and lower lines are ‘n’ standard deviations above and below the SMA, respectively. Calculating Bollinger Bands is fairly straightforward: - Calculate a simple moving average of the asset’s price over a specific time period. - Calculate standard deviation over the same time period. - Draw lines 'n' standard deviation above and below the SMA to get the upper and lower bands. ## FAQs ### What are Bollinger Bands? Bollinger Bands are a volatility indicator created by [John Bollinger](https://www.bollingerbands.com/). Bollinger Bands consist of a [simple moving average (SMA)](https://optionalpha.com/learn/simple-moving-average) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two [standard deviations](https://optionalpha.com/topics/financial-modeling). ### How to read Bollinger Bands? The main purpose of Bollinger Bands is to provide traders with a relative definition of high and low prices for a given market. By definition, prices are high at the upper band and low at the lower band. This information can be used to determine whether prices are relatively high or low in comparison to past price action. Price tends to oscillate within the bands and the upper and lower bands can be used as resistance and support. Breakouts above the upper band or below the lower band are often used as trading signals. ### How do you use Bollinger bands? Bollinger bands are used to measure price volatility. When the bands widen, price volatility is increasing and when the bands contract, volatility is decreasing. You can use Bollinger Bands to identify price action that is overextended. [Mean reversion](https://optionalpha.com/learn/mean-reversion) and [trend following](https://optionalpha.com/topics/trend-trading) traders use Bollinger Bands to go long or short a security based on their interpretation of the trading signal. ### How Accurate are Bollinger Bands? Bollinger Bands are a reliable and effective tool for measuring market volatility. They provide traders with an objective measure of whether prices are high or low on a relative basis. Bollinger Bands are a lagging indicator but they're a popular tool due to their simplicity and effectiveness in gauging market volatility. Traders can combine them with other [technical indicators](https://optionalpha.com/topics/technical-indicators) to predict future price movements. Contributors [![Steve Henry](https://cdn.prod.website-files.com/5fba23eb8789c3c7fcfb5f31/607d8edd49b20c84ee842820_Steve-Henry-Avatar.png)Steve Henry Content Director](https://optionalpha.com/team/steve-henry) [![Kirk Du Plessis](https://cdn.prod.website-files.com/5fba23eb8789c3c7fcfb5f31/622fa2005a5fabed64659616_607d8ea5221240c8618ea3d1_Kirk-Du-Plessis-Avatar%20\(1\).png)Kirk Du Plessis Founder](https://optionalpha.com/team/kirk-duplessis) Last updated: May 15, 2023 Sep 13, 2023 Originally published: May 15, 2023 [Technical Indicators](https://optionalpha.com/tags/technical-indicators) [Technical Analysis](https://optionalpha.com/tags/technical-analysis) [SMA](https://optionalpha.com/tags/sma) [Volatility](https://optionalpha.com/tags/volatility) Highlights - Bollinger Bands measure a security's price volatility. - Bollinger Bands use a simple moving average and standard deviation. - Traders use Bollinger Bands as a trend following or mean reversion trading signal. On this page [Example H2](https://optionalpha.com/learn/bollinger-bands) [Example H3](https://optionalpha.com/learn/bollinger-bands) [Example H4](https://optionalpha.com/learn/bollinger-bands) [FAQs](https://optionalpha.com/learn/bollinger-bands) Popular... [![](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/641de0644de07e3f3767b593_CleanShot%202023-03-24%20at%2013.20.01%402x.png)GuidesAutotrading Quick-StartThis 4-part guide shows you how to safely get started with automated trading by the end of the day.](https://optionalpha.com/learn/bollinger-bands) [Watch Now](https://optionalpha.com/learn/bollinger-bands) ![](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/672928e7bf3c2c6cda7cd914_Trade%20with%20conviction.png) Trade with conviction Find an edge backtesting 0DTE and next day strategies using 1 minute data then leverage automation to execute your strategy better than humanly possible. [Start My Free Trial](https://optionalpha.com/start) ## You might also like Our philosophy is simple — publish options education that's better than everyone else. No ads, no fluff, no subjective bias; just the facts beautifully organized for you. [![](https://cdn.prod.website-files.com/5fba23eb8789c3c7fcfb5f31/630f3030c0454ef8b770b05f_file-05.svg) Learn how to automate a Bollinger Band strategy This blog shows you how to build a bot using debit and credit spreads to trade breakouts.Read more](https://optionalpha.com/blog/how-to-automate-a-bollinger-band-strategy) [![](https://cdn.prod.website-files.com/5fba23eb8789c3c7fcfb5f31/630f2f929fdc655f4b40d7a2_book-open-01.svg) Here's your complete guide to trading option spreads This page has everything you need to know about short put spreads and short call spreadsRead more](https://optionalpha.com/learn/vertical-spread) ###### Trade with discipline and consistency Find opportunities. Backtest ideas. Automate strategies. [Learn more](https://optionalpha.com/backtester-start) [Start Free Trial](https://optionalpha.com/start) ![MacBook mockup](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/69bf495868c38bcbe09ef10e_tradeideas.png) [![Option Alpha logo](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/635030ca6aea371383d0ef5b_oa%20logo%203x%20-%20white.png)](https://optionalpha.com/) - [![Facebook Icon](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/5fba23eb8789c366fcfb5fb6_facebook.svg)](https://www.facebook.com/OptionAlphaCompany) - [![Instagram Icon](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/5fba23eb8789c34ca5fb5f98_instagram.svg)](https://www.instagram.com/optionalpha/) - [![Youtube Icon](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/5fba23eb8789c3a9b3fb5f72_youtube.svg)](https://www.youtube.com/OptionAlpha?sub_confirmation=1) - [![LinkedIn Icon](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/5fba23eb8789c37ad3fb5f74_linkedin.svg)](https://www.linkedin.com/company/optionalpha) - [![Twitter Icon](https://cdn.prod.website-files.com/5fba23ebc651c6d16f446fc4/5fba23eb8789c359d0fb5f7a_twitter.svg)](https://twitter.com/OptionAlpha) ###### Platform - [Bots](https://optionalpha.com/bots) - [Templates](https://optionalpha.com/templates) - [Integrations](https://optionalpha.com/integrations) - [Backtester](https://optionalpha.com/backtester) - [Community](https://optionalpha.com/community) ###### Resources - [Bots 101](https://optionalpha.com/bots-101) - [Workshops](https://app.livestorm.co/optionalpha) - [Videos](https://optionalpha.com/videos) ###### Education - [Courses](https://optionalpha.com/courses) - [Strategies](https://optionalpha.com/options-strategies) - [Handbook](https://optionalpha.com/handbook) - [Podcast](https://optionalpha.com/podcast) - [Blog](https://optionalpha.com/blog) ###### Company - [About](https://optionalpha.com/about-us) - [Careers](https://optionalpha.com/careers) - [Team](https://optionalpha.com/team) - [Legal](https://optionalpha.com/legal) - [Help](https://docs.optionalpha.com/) - [Contact](https://optionalpha.com/contact) - [Status](https://status.optionalpha.com/) © 2026 Option Alpha. All Rights Reserved. Patent Pending USSN 63/118,547 [![California Consumer Privacy Act (CCPA) Opt-Out Icon](<data:image/svg+xml;charset=UTF-8,%3csvg version='1.1' id='Layer_1' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' x='0px' y='0px' viewBox='0 0 30 14' style='enable-background:new 0 0 30 14;' xml:space='preserve'%3e%3cstyle type='text/css'%3e .st0%7bfill-rule:evenodd;clip-rule:evenodd;fill:%23FFFFFF;%7d .st1%7bfill-rule:evenodd;clip-rule:evenodd;fill:%230066FF;%7d .st2%7bfill:%23FFFFFF;%7d .st3%7bfill:%230066FF;%7d %3c/style%3e%3cg%3e%3cg id='final---dec.11-2020_1_'%3e%3cg id='_x30_208-our-toggle_2_' transform='translate(-1275.000000, -200.000000)'%3e%3cg id='Final-Copy-2_2_' transform='translate(1275.000000, 200.000000)'%3e%3cpath class='st0' d='M7.4,12.8h6.8l3.1-11.6H7.4C4.2,1.2,1.6,3.8,1.6,7S4.2,12.8,7.4,12.8z'/%3e%3c/g%3e%3c/g%3e%3c/g%3e%3cg id='final---dec.11-2020'%3e%3cg id='_x30_208-our-toggle' transform='translate(-1275.000000, -200.000000)'%3e%3cg id='Final-Copy-2' transform='translate(1275.000000, 200.000000)'%3e%3cpath class='st1' d='M22.6,0H7.4c-3.9,0-7,3.1-7,7s3.1,7,7,7h15.2c3.9,0,7-3.1,7-7S26.4,0,22.6,0z M1.6,7c0-3.2,2.6-5.8,5.8-5.8 h9.9l-3.1,11.6H7.4C4.2,12.8,1.6,10.2,1.6,7z'/%3e%3cpath id='x' class='st2' d='M24.6,4c0.2,0.2,0.2,0.6,0,0.8l0,0L22.5,7l2.2,2.2c0.2,0.2,0.2,0.6,0,0.8c-0.2,0.2-0.6,0.2-0.8,0 l0,0l-2.2-2.2L19.5,10c-0.2,0.2-0.6,0.2-0.8,0c-0.2-0.2-0.2-0.6,0-0.8l0,0L20.8,7l-2.2-2.2c-0.2-0.2-0.2-0.6,0-0.8 c0.2-0.2,0.6-0.2,0.8,0l0,0l2.2,2.2L23.8,4C24,3.8,24.4,3.8,24.6,4z'/%3e%3cpath id='y' class='st3' d='M12.7,4.1c0.2,0.2,0.3,0.6,0.1,0.8l0,0L8.6,9.8C8.5,9.9,8.4,10,8.3,10c-0.2,0.1-0.5,0.1-0.7-0.1l0,0 L5.4,7.7c-0.2-0.2-0.2-0.6,0-0.8c0.2-0.2,0.6-0.2,0.8,0l0,0L8,8.6l3.8-4.5C12,3.9,12.4,3.9,12.7,4.1z'/%3e%3c/g%3e%3c/g%3e%3c/g%3e%3c/g%3e%3c/svg%3e>) Your Privacy Choices](https://optionalpha.com/learn/bollinger-bands) [Notice at Collection](https://optionalpha.com/learn/bollinger-bands)
Readable Markdown	Bollinger Bands are a volatility indicator created by [John Bollinger](https://www.bollingerbands.com/). Bollinger Bands consist of a [simple moving average (SMA)](https://optionalpha.com/learn/simple-moving-average) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two [standard deviations](https://optionalpha.com/topics/financial-modeling). The bands are dynamic and display changes in volatility. They widen when price volatility is increasing and contract when volatility decreases, allowing traders to quickly identify periods of high and low volatility. ![Bollinger Bands](https://cdn.prod.website-files.com/5fba23eb8789c3c7fcfb5f31/64627b34b8470bc52cbb54ab_Bollinger%20Bands.jpeg) Bollinger Bands provide a relative definition of high and low prices for a given ticker symbol. By definition, prices are considered high at the upper band and low at the lower band. Traders can use this information to determine whether prices are relatively high or low in comparison to past price action. If the bands are drawn two standard deviations above and below the center simple moving average, approximately 95% of the security’s price action should occur within the bands. ![Standard Deviation](https://cdn.prod.website-files.com/5fba23eb8789c3c7fcfb5f31/64627b4eb8470bc52cbb6dc4_StandardDeviation.png) Price moving above the upper band or below the lower band is often used as trading signal. Price tends to oscillate within the bands, so the upper and lower bands can be used as resistance and support or as a breakout signal. When combined with other [technical indicators](https://optionalpha.com/topics/technical-indicators), such as [MACD](https://optionalpha.com/learn/macd-indicator) and [RSI](https://optionalpha.com/learn/rsi-indicator), Bollinger Bands can help identify overbought/oversold conditions, trend reversals, continuation, and more. Bollinger bands are used to measure volatility and define potential price channels or [trends](https://optionalpha.com/topics/trend-trading). When prices move outside the bands, it can indicate that a new trend is beginning or that prices have become overextended. There are many Bollinger Bands strategies and traders use the indicator several ways. [Mean reversion](https://optionalpha.com/learn/mean-reversion) traders may buy the security when its price touches the lower band and sell when price hits the upper band. Conversely, [momentum traders](https://optionalpha.com/topics/momentum-trading) could use the bands as a signal that price will continue and buy near the upper band or sell near the lower band. ## Calculating Bollinger Bands Bollinger Bands consist of three lines. The middle line is a simple moving average (SMA) and the upper and lower lines are ‘n’ standard deviations above and below the SMA, respectively. Calculating Bollinger Bands is fairly straightforward: - Calculate a simple moving average of the asset’s price over a specific time period. - Calculate standard deviation over the same time period. - Draw lines 'n' standard deviation above and below the SMA to get the upper and lower bands. FAQs ### What are Bollinger Bands? Bollinger Bands are a volatility indicator created by [John Bollinger](https://www.bollingerbands.com/). Bollinger Bands consist of a [simple moving average (SMA)](https://optionalpha.com/learn/simple-moving-average) and two bands above and below the SMA. Typically, the centerline is a 20-day moving average and the bands are two [standard deviations](https://optionalpha.com/topics/financial-modeling). ### How to read Bollinger Bands? The main purpose of Bollinger Bands is to provide traders with a relative definition of high and low prices for a given market. By definition, prices are high at the upper band and low at the lower band. This information can be used to determine whether prices are relatively high or low in comparison to past price action. Price tends to oscillate within the bands and the upper and lower bands can be used as resistance and support. Breakouts above the upper band or below the lower band are often used as trading signals. ### How do you use Bollinger bands? Bollinger bands are used to measure price volatility. When the bands widen, price volatility is increasing and when the bands contract, volatility is decreasing. You can use Bollinger Bands to identify price action that is overextended. [Mean reversion](https://optionalpha.com/learn/mean-reversion) and [trend following](https://optionalpha.com/topics/trend-trading) traders use Bollinger Bands to go long or short a security based on their interpretation of the trading signal. ### How Accurate are Bollinger Bands? Bollinger Bands are a reliable and effective tool for measuring market volatility. They provide traders with an objective measure of whether prices are high or low on a relative basis. Bollinger Bands are a lagging indicator but they're a popular tool due to their simplicity and effectiveness in gauging market volatility. Traders can combine them with other [technical indicators](https://optionalpha.com/topics/technical-indicators) to predict future price movements.
Shard	72 (laksa)
Root Hash	6261014955454694472
Unparsed URL	com,optionalpha!/learn/bollinger-bands s443