Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression

/
/
gm

Test String

Code Generator

Generated Code

const regex = /<div\sid=\"[\s\S]*?dp_productDescription_container_div[\s\S]*?<div\sid=\"productDescription_feature_div[\s\S]*?<div[\s\S]*?<div[\s\S]*?<div\sid=\"productDescription[\s\S]*?>([\s\S]*?<p>[\s\S]*?<\/p>\s*)<\/div>/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('<div\\sid=\\"[\\s\\S]*?dp_productDescription_container_div[\\s\\S]*?<div\\sid=\\"productDescription_feature_div[\\s\\S]*?<div[\\s\\S]*?<div[\\s\\S]*?<div\\sid=\\"productDescription[\\s\\S]*?>([\\s\\S]*?<p>[\\s\\S]*?<\\\/p>\\s*)<\\\/div>', 'gm') const str = `<div id="dp_productDescription_container_div" class="feature" data-feature-name="productDescription" data-cel-widget="dp_productDescription_container_div"> <div id="productDescription_feature_div" data-feature-name="productDescription" data-template-name="productDescription" class="a-row feature" data-cel-widget="productDescription_feature_div"> <div class="a-divider a-divider-section"><div class="a-divider-inner"></div></div> <h2 class="softlines"> Product description </h2> <div id="productDescription" class="a-section a-spacing-small"> <!-- show up to 2 reviews by default --> <p>Train better. Look great. The Vazee agility trainer supports your interval workouts with an exciting blend of fashionable colors and a newly designed performance lace mesh upper for support and breathability. </p> <p>Train better. Look great. The Vazee agility trainer supports your interval workouts with an exciting blend of fashionable colors and a newly designed performance lace mesh upper for support and breathability. </p> </div> <style type="text/css"> #productDescription { color: #333333; word-wrap: break-word; font-size: small; line-height: initial; margin: 0.5em 0px 0em 25px; } #productDescription_feature_div > h2.default { color: #CC6600; font-size: medium; margin: 0 0 0.25em; } #productDescription_feature_div > h2.books { color:#333 !important; font-size:21px !important; line-height: 1.3; padding-bottom: 4px; font-weight: normal; margin: 0px; } #productDescription_feature_div > h2.softlines { color:#333 !important; font-size:21px !important; line-height: 1.3; padding-bottom: 4px; font-weight: bold; margin: 0px; } #productDescription > p, #productDescription > div, #productDescription > table { margin: 0 0 1em 0; } #productDescription p { margin: 0em 0 1em 1em; } #productDescription h3 { font-weight: normal; color: #333333; font-size: 1.23em; clear: left; margin: 0.75em 0px 0.375em -15px; } #productDescription table { border-collapse: inherit !important; margin-bottom: 0; } #productDescription table img { max-width: inherit !important; } #productDescription table td { font-size: small; vertical-align: inherit !important; } #productDescription ul li { margin: 0 0 0 20px; } #productDescription ul li ul { list-style-type: disc !important; margin-left: 20px !important; } #productDescription ul ul li { list-style-type: disc !important; margin-left: 20px !important; } #productDescription > ul ul li { list-style-type: disc !important; } #productDescription ul li ul li { margin: 0 0 0 20px; } #productDescription .aplus p { margin: 0 0 1em 0; } #productDescription small { font-size: smaller; } #productDescription.prodDescWidth { max-width: 1000px } </style> <!-- Used to set table width because AUI is overriding the width attribute of the tables coming in description --> <script type="text/javascript"> P.when('jQuery').execute(function(\$){ \$("#productDescription table").each(function() { var width = \$(this).attr('width'); if (width) width += 'px'; else width = 'auto'; \$(this).css('width', width); var padding = \$(this).attr('cellpadding'); if (padding) padding += 'px'; else padding = '0px'; \$(this).css('padding', padding); }); }); </script> </div> </div>`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions