Regular Expressions 101

Save & Manage Regex

  • Current Version: 1
  • Save & Share
  • Community Library

Flavor

  • PCRE2 (PHP)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java
  • .NET 7.0 (C#)
  • Rust
  • PCRE (Legacy)
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests
Sponsors
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
Processing...

Test String

Substitution
Processing...

Code Generator

Language

Generated Code

const regex = /^(♪\h+[A-Za-z].*?(?:\R[A-Za-z].*?)?)♪?$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(♪\\h+[A-Za-z].*?(?:\\R[A-Za-z].*?)?)♪?$', 'gm') const str = `============================== BEFORE ============================== 400 00:31:44,633 --> 00:31:45,716 Come on. 401 00:31:59,940 --> 00:32:02,399 Caleb used to do that when he ate. 402 00:32:03,902 --> 00:32:05,069 Pull my hair like that. 410 00:32:46,653 --> 00:32:48,654 ♪ Saying</i> 411 00:32:48,738 --> 00:32:52,241 ♪ This is my message to you</i> 412 00:32:56,163 --> 00:32:57,538 ♪ Don't worry</i> 636 00:55:59,545 --> 00:56:02,296 ♪ You don't own me 637 00:56:02,798 --> 00:56:06,676 ♪ I'm not just one of your many toys 638 00:56:06,969 --> 00:56:09,929 ♪ You don't own me 639 00:56:10,347 --> 00:56:16,394 ♪ Don't say I can't go with other boys 640 00:56:16,728 --> 00:56:20,106 ♪ And don't tell me what to do 641 00:56:20,816 --> 00:56:24,026 ♪ Don't tell me what to say ♪ 642 00:56:24,278 --> 00:56:27,822 ♪ And please, when I go out with you ♪ 643 00:56:28,365 --> 00:56:31,742 ♪ Don't put me on display ♪ 644 00:56:31,952 --> 00:56:36,080 ♪ 'Cause you don't own me ♪`; const subst = `$1 ♪`; // The substituted value will be contained in the result variable const result = str.replace(regex, subst); console.log('Substitution result: ', result);

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