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

/
/
g

Test String

Code Generator

Generated Code

const regex = /<script.*src.*edge.*<\/script>/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('<script.*src.*edge.*<\\\/script>', 'g') const str = `<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> <meta http-equiv="X-UA-Compatible" content="IE=Edge"/> <title>Untitled</title> <!--Adobe Edge Runtime--> <meta http-equiv="X-UA-Compatible" content="IE=Edge"> <script src="//ad.adverticum.net/scripts/goa-helper.js"></script> <script type="text/javascript" charset="utf-8" src="http://animate.adobe.com/runtime/5.0.0/edge.5.0.0.min.js"></script> <style> .edgeLoad-EDGE-20744748 { visibility:hidden; } </style> <script> AdobeEdge.loadComposition('MM_Gyor_Huawei_1112-1114_HTML5_720x250', 'EDGE-20744748', { scaleToFit: "none", centerStage: "both", minW: "0", maxW: "undefined", width: "720px", height: "250px" }, {"dom":{}}, {"dom":{}}); </script> <!--Adobe Edge Runtime End--> </head> <body style="margin:0;padding:0;"> <div id="Stage" class="EDGE-20744748"></div> </body> </html>`; // 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