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

r"
"
gmx

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('(?<!d)(?: (?:(?:0?[1-9]|[12]\\d)|3[01])\\s?[./:-][\\s.]?(?:0?[13578]|1[02]|J(?:an(?:uar)?|uli?)|M(?:ärz?|ai)|Aug(?:ust)?|Dez(?:ember)?|Okt(?:ober)?)\\s?(?:[./:-][\\s.]?)?[1-9]\\d\\d\\d| (?:(?:0?[1-9]|[12]\\d)|30)\\s?[./:-][\\s.]?(?:0?[13-9]|1[012]|J(?:an(?:uar)?|u[nl]i?)|M(?:ärz?|ai)|A(?:pr(?:il)?|ug(?:ust)?)|Sep(?:tember)?|(?:Nov|Dez)(?:ember)?|Okt(?:ober)?)\\s?(?:[./:-][\\s.]?)?[1-9]\\d\\d\\d| (?:0?[1-9]|[12]\\d)\\s?[./:-][\\s.]?(?:0?2|Fe(?:b(?:ruar)?)?)\\s?(?:[./:-][\\s.]?)?[1-9]\\d(?:[02468][048]|[13579][26])| (?:0?[1-9]|[12][0-8])\\s?[./:-][\\s.]?(?:0?2|Fe(?:b(?:ruar)?)?)\\s?(?:[./:-][\\s.]?)?[1-9]\\d\\d\\d )(?!\\d)', 'gm') const str = `12.12.2021 09. Juni 1997 01.Aug.1995 27.06. 1997 29.02.1996 21. 01. 1999 28.05. 1996 07..4..1995 20:03:1998 9.4.1997 14 .03 - 1995 Month regex is tested at https://regex101.com/r/tClRRs/2 (?:J(?:an(?:uar)?|u[nl]i?)|Fe(?:b(?:ruar)?)?|M(?:ärz?|ai)|A(?:pr(?:il)?|ug(?:ust)?)|Sep(?:tember)?|(?:Nov|Dez)(?:ember)?|Okt(?:ober)?) Taking out Feb: (?:J(?:an(?:uar)?|u[nl]i?)|M(?:ärz?|ai)|A(?:pr(?:il)?|ug(?:ust)?)|Sep(?:tember)?|(?:Nov|Dez)(?:ember)?|Okt(?:ober)?) `; // 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