Regular Expressions 101

Save & Share

  • Regex Version: ver. 1
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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 = /^((?<emoji_left>(?::\w*:|\ud83c[\udf00-\udfff]|\ud83d[\udc00-\ude4f\ude80-\udeff]|[\u2600-\u2B55]))\s)?(?<type>\w+)(?:\((?<scope>[^)]*)\))?!?:\s((?<emoji_center>(?::\w*:|\ud83c[\udf00-\udfff]|\ud83d[\udc00-\ude4f\ude80-\udeff]|[\u2600-\u2B55]))\s)?(?<subject>(?:(?!#).)*(?:(?!\s).))(?:\s(?<ticket>#(?<ticket_number>\w+)|\(#(?<ticket_number>\w+)\)))?(?:\s(?<emoji_right>(?::\w*:|\ud83c[\udf00-\udfff]|\ud83d[\udc00-\ude4f\ude80-\udeff]|[\u2600-\u2B55])))?$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^((?<emoji_left>(?::\\w*:|\\ud83c[\\udf00-\\udfff]|\\ud83d[\\udc00-\\ude4f\\ude80-\\udeff]|[\\u2600-\\u2B55]))\\s)?(?<type>\\w+)(?:\\((?<scope>[^)]*)\\))?!?:\\s((?<emoji_center>(?::\\w*:|\\ud83c[\\udf00-\\udfff]|\\ud83d[\\udc00-\\ude4f\\ude80-\\udeff]|[\\u2600-\\u2B55]))\\s)?(?<subject>(?:(?!#).)*(?:(?!\\s).))(?:\\s(?<ticket>#(?<ticket_number>\\w+)|\\(#(?<ticket_number>\\w+)\\)))?(?:\\s(?<emoji_right>(?::\\w*:|\\ud83c[\\udf00-\\udfff]|\\ud83d[\\udc00-\\ude4f\\ude80-\\udeff]|[\\u2600-\\u2B55])))?$', 'gm') const str = `chore(scope): test chore(scope)!: test chore!: test chore!(scope)!: test hello: :test: test #111 ✨ :start: test: 1wsdwqs #11111 ✨ feat(unicode): ✨ adasas sfsd :das: #1d1w ✨ feat(unicode): add unicode suppdadass o # (#rtasa) ✨ :hello: test: test :start: chore(scope): test :start: chore(scope): test #123 :memo: docs: update README.md :start: chore(scope): i have a word #123 :package: feat(parser-opts): extract parser-opts packages :sparkles: feat(changelog): 添加中文标题 :sparkles: feat(changelog): add chinese title ✨ feat(unicode): add unicode support 😌 test(only): add unicode support :sparkles: feat: hello world (#100) `; // 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