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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

const regex = /^[\d\n].*\n/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^[\\d\\n].*\\n', 'gm') const str = `1 00:00:01.876 --> 00:00:02.709 <v Instructor>We can go back now</v> 2 00:00:02.709 --> 00:00:05.042 to our web server checklist. 3 00:00:06.410 --> 00:00:08.722 We've already seen better ways to organise our code 4 00:00:08.722 --> 00:00:11.545 into reusable pieces with modules, 5 00:00:11.545 --> 00:00:13.315 we've seen ways to deal with files, 6 00:00:13.315 --> 00:00:15.940 both synchronous and asynchronous, 7 00:00:15.940 --> 00:00:16.773 and buffers, 8 00:00:16.773 --> 00:00:18.325 both the built-in Node one 9 00:00:18.325 --> 00:00:20.380 and the ES6 buffers, 10 00:00:20.380 --> 00:00:22.485 and we've seen a way to deal with work`; const subst = ``; // 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