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
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /(?>(\b(?:(?:[0-9]{7}|[0-9]{10,11})|[a-zA-Z][0-9]{10})\b)[^\r\n]*?(\b(?:\d{1,2}|(?:(?:Jan(?:uary)?|Feb(?:ruary)?|Mar(?:ch)?|Apr(?:il)?|May|Jun(?:e)?|Jul(?:y)?|Aug(?:ust)?|Sep(?:tember|(?:t\.?|\.))?|Oct(?:ober|\.)?|Nov(?:ember|\.)?|Dec(?:ember|\.)?)))(?:[^A-Za-z0-9\v](?:\d{1,2})\,?[^A-Za-z0-9\v](?:\d{2}|\d{4})|[^A-Za-z0-9\v\.](?:(?:\'|\`)\d{2}|\d{4}))\b)[^\r\n]*?(\$\d+[\.\,\d]*)[^\r\n]*?($))|(?2)[^\r\n]*?(?:(?1)|(?3))[^\r\n]*?(?4)|(?1)[^\r\n]*?(?:(?2)|(?3))[^\r\n]*?(?4)|(?3)[^\r\n]*?(?:(?1)|(?2))[^\r\n]*?(?4)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?>(\\b(?:(?:[0-9]{7}|[0-9]{10,11})|[a-zA-Z][0-9]{10})\\b)[^\\r\\n]*?(\\b(?:\\d{1,2}|(?:(?:Jan(?:uary)?|Feb(?:ruary)?|Mar(?:ch)?|Apr(?:il)?|May|Jun(?:e)?|Jul(?:y)?|Aug(?:ust)?|Sep(?:tember|(?:t\\.?|\\.))?|Oct(?:ober|\\.)?|Nov(?:ember|\\.)?|Dec(?:ember|\\.)?)))(?:[^A-Za-z0-9\\v](?:\\d{1,2})\\,?[^A-Za-z0-9\\v](?:\\d{2}|\\d{4})|[^A-Za-z0-9\\v\\.](?:(?:\\\'|\\`)\\d{2}|\\d{4}))\\b)[^\\r\\n]*?(\\$\\d+[\\.\\,\\d]*)[^\\r\\n]*?($))|(?2)[^\\r\\n]*?(?:(?1)|(?3))[^\\r\\n]*?(?4)|(?1)[^\\r\\n]*?(?:(?2)|(?3))[^\\r\\n]*?(?4)|(?3)[^\\r\\n]*?(?:(?1)|(?2))[^\\r\\n]*?(?4)', 'gm') const str = `9991110022 9/4/2019 9/12/2019 \$10403.33 10/2/2019 11/2/2019 33300011113 \$130.30 12200013131 Nov. 2, 2019 \$45,300.32 9991110022 9/4/2019 9/12/2019 \$10403.33 \$492,300 10/2/2019 11/2/2019 33300011113 5/3/2019 \$500.30 12200013131 Nov. 2, 2019 \$45,300.32`; // 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