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 = /[\da-fA-F]{8}-[\da-fA-F]{4}-[\da-fA-F]{4}-[\da-fA-F]{4}-[\da-fA-F]{12}/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('[\\da-fA-F]{8}-[\\da-fA-F]{4}-[\\da-fA-F]{4}-[\\da-fA-F]{4}-[\\da-fA-F]{12}', 'gm') const str = `4af06d20-10d5-4d9f-bfce-ca2724a82803 2a3e42b3-f3d44501-89ee-835164dcecd6f (-f3d44501-) d7e3c311-b5b4-4c9f-a3df-a56b8512f60b 2193cf3f-8da8-4d8a-9103-c91cca66889c 80112dcf-bec8-428d-8f0-b4fd0ca506d5c (-8f0-) {a8fbdb9f-56ac-44c9-a74f-21b393e57e57} 51b16c80-901c-4270-93a7-120a8cGb42ab ("G") e257613b-ca10-412e-aeaf-0597db11162c 4ed178df-7575-457f-aef1-03b44b68e55H ("H") a5E5108-5e54-4-28-b406-83a2-9a711bc4 (-4-28-) Power Scheme GUID: 0f916538-c8d5-4144-be2a-ee82eccf6413 `; // 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