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

/
/
g

Test String

Code Generator

Language

Generated Code

$re = '/(https?\:\/\/(?:[[:alnum:]]+\.)?[[:alnum:]]+\.(?:com|net|org)\/\S*)|(https?\:\/\/(?:\d{1,3}\.){3}\d{1,3}\/?(?:\:\d{0,6})?\/?)/'; $str = 'Screen 0: minimum 320 x 200, current 3520 x 1080, maximum 8192 x 8192 VGA-0 connected 1600x900+1920+180 (normal left inverted right x axis y axis) 443mm x 249mm 1600x900 60.00*+ 75.00 1280x1024 75.02 70.00 60.02 1440x900 59.89 1280x800 59.81 1152x864 75.00 1280x720 59.97 1024x768 75.08 70.07 60.00 832x624 74.55 800x600 72.19 75.00 60.32 56.25 640x480 75.00 72.81 60.00 720x400 70.08 LVDS connected (normal left inverted right x axis y axis) 1366x768 59.97 + 1280x720 59.86 1152x768 59.78 1024x768 59.92 800x600 59.86 848x480 59.66 720x480 59.71 640x480 59.38 HDMI-0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 1150mm x 650mm 1360x768 60.02 + 1920x1080 60.00* 59.94 30.00 24.00 29.97 23.98 1920x1080i 60.00 59.94 1280x1024 60.02 1280x720 60.00 59.94 1024x768 60.00 800x600 60.32 720x480 60.00 59.94 640x480 60.00 59.94 59.94 720x400 70.08 https://www.example.com/foo/?bar=baz&inga=42&quux http://✪df.ws/123 http://userid:password@example.com:8080 http://userid:password@example.com:8080/ http://userid@example.com http://userid@example.com/ http://userid@example.com:8080 http://userid@example.com:8080/ http://userid:password@example.com http://userid:password@example.com/ http://142.42.1.1/ http://142.42.1.1:8080/ http://➡.ws/䨹 http://⌘.ws http://⌘.ws/ http://foo.com/blah_(wikipedia)#cite-1 http://foo.com/blah_(wikipedia)_blah#cite-1 http://foo.com/unicode_(✪)_in_parens http://foo.com/(something)?after=parens http://☺.damowmow.com/ http://code.google.com/events/#&product=browser http://j.mp ftp://foo.com/baz http://foo.bar/?q=Test%20URL-encoded%20stuff http://مثال.إختبار http://例子.测试 http://उदाहरण.परीक्षा http://-.~_!$&\'()*+,;=:%40:80%2f::::::@example.com http://1337.net http://a.b-c.de http://223.255.255.254 SHOULD NOT MATCH: http:// http://. http://.. http://../ http://? http://?? http://??/ http://# http://## http://##/ http://foo.bar?q=Spaces should be encoded // //a ///a /// http:///a foo.com rdar://1234 h://test http:// shouldfail.com :// should fail http://foo.bar/foo(bar)baz quux ftps://foo.bar/ http://-error-.invalid/ http://a.b--c.de/ http://-a.b.co http://a.b-.co http://0.0.0.0 http://10.1.1.0 http://10.1.1.255 http://224.1.1.1 http://1.1.1.1.1 http://123.123.123 http://3628126748 http://.www.foo.bar/ http://www.foo.bar./ http://.www.foo.bar./ http://10.1.1.1 '; 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