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
  • 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

$re = '/\b([0-9]{1,2})\.[0-9]{1,2}\.[0-9]{3,4}[\.]{0,1}[0-9]{0,4}/m'; $str = 'Microsoft SQL Server 2008 (SP1) - 10.0.2531.0 (X64) Mar 29 2009 10:11:52 Copyright (c) 1988-2008 Microsoft Corporation Express Edition (64-bit) on Windows NT 6.1 <X64> (Build 7600: ) ↓SQL Server 2016 – 13.00.900.73 (CTP3.2) ↓SQL Server 2014 12.00.2000.8 12.0.4100.1 12.0.4436.0 (SP1 CU4) ↓SQL Server 2012 11.00.2100.60 11.00.3000 11.00.5058 11.00.6020 11.0.6020 (SP3) ↓SQL Server 2008R2 10.50.1600.1 10.50.2500 10.50.4000 10.50.6000 10.50.6529 (MS15-058) ↓SQL Server 2008 10.00.1600.22 10.00.2531 10.00.4000 10.00.5500 10.00.6000 10.00.6535 (MS15-058) ↓SQL Server 2005 9.00.1399.06 9.00.2047 9.00.3042 9.00.4035 9.00.5000 9.00.5324 (MS12-070) ↓SQL Server 2000 8.00.194 8.00.384 8.00.532 8.00.760 8.00.2039 8.00.2305 (MS12-060) ↓SQL Server 7.0 7.0.623 7.0.699 7.0.842 7.00.961 7.00.1063 7.00.1152 (MS08-040)'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php