Regular Expressions 101

Save & Share

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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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"
"
gm

Test String

Code Generator

Generated Code

const regex = new RegExp('^(\\w+(\\-\\w+)?)(\\s)([A-Z]\\.\\s)*(\\w+)(\\s\\w+)?\\,((\\(|1\\-|\\(1\\-)*\\d{3}(\\)(\\s)?|-|\\s|\\)\\-)?\\d{3}\\-*\\s?\\d{4})\\,(\\w+)(\\-\\w+\\-\\w+)?(\\s\\w+$)?', 'gm') const str = `Kiayada D. Levy,(570)7924192,Sint-Laureins-Berchem Gretchen F. Manning,(1-656)-285-0869,Spoleto Ashton Richards,(974) 843-9297,Annapolis Royal Demetrius J. Ferguson,1-906-206-4323,Rea Blair Nelson,1-121-171-3665,Bertiolo Cynthia J. Farley,632 691 2180,Moen Nayda M. Lloyd,1-864-250-6977,Sarrev Miranda Edith Sexton,1-597-689-8316,Shipshaw Fulton Mays,(725)789-9517,Pierrefonds Shea Kim,1-697-854-4139,Bihain Emma-Mae Winters,1-137-630-5601,Gulfport Inez W. Depew,1-833-470-5664,Johnstone Darrel F. Key,1-878-918-2161,Olympia Tobias L. Stephens,1-119-939-6704,Unnao Elmo Pate,1-869-333-7341,Griesheim`; 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