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

/
/
gm

Test String

Code Generator

Language

Generated Code

$re = '/^\(\s*([0-9]+)\)\[([a-zA-Z0-9\s*:]*)\|\s*([0-9]{1,5}\:[0-9]{3})\s*(?:\[([0-9]{1,3})\:[0-9]{1,3}\])?\]\{([0-9]{1,4})\}([a-zA-Z0-9]+)\@([a-zA-Z0-9]+)\:(.+)\((?:.+)\)([\$|#])\s{1}(.+)(\n(.+))+/m'; $str = '( 6)[Thu Sep 01 04:47:12| 2:000]{1}jhyland@jhmac:~(✓)$ ls Applications kn Public bash_profile.orig pdfdata.json search_src-printr.txt vim-colorschemes BaseServer.py LDEV-342302 VirtualBox VMs file.py pipe1 search_src.json vim-config Desktop Library _includexmlrpc.php filename.txt profile-configs test.php vimrc.disabled Documents Movies _includexmlrpc.php.original gvimrc.disabled profile-configs-orig test.txt Downloads Music _includexmlrpc.php.original2 index.php protected_backup.tar.gz tester Google Drive Pictures as.txt items.php.orig search-stuff.js tmp InventoryServer.py ProblemServer.py.new-working bash_profile new.bash_profile search_src-20.json tmp.txt ( 6)[Thu Sep 01 04:47:13| 0:000]{2}jhyland@jhmac:~(✓)$ cd /tmp ( 6)[Thu Sep 01 04:47:18| 0:000]{3}jhyland@jhmac:/tmp(✓)$ ls | wc -l 15 ( 6)[Thu Sep 01 04:47:22| 0:000]{4}jhyland@jhmac:/tmp(✓)$ sudo su - ( 6)[Thu Sep 01 04:47:25| 0:000]{1}root@jhmac:~(✓)# whoami root ( 6)[Thu Sep 01 04:47:28| 0:000]{2}root@jhmac:~(✓)# history | tail -n 2 393 whoami 394 history | tail -n 2 ( 6)[Thu Sep 01 04:47:39| 0:000]{3}root@jhmac:~(✓)# ( 6)[Thu Sep 01 04:47:40| 0:000]{3}root@jhmac:~(✓)# fail -sh: fail: command not found ( 6)[Thu Sep 01 04:47:44| 0:000]{4}root@jhmac:~(127)# ( 6)[Thu Sep 01 04:47:44| 0:000]{4}root@jhmac:~(127)# ( 6)[Thu Sep 01 04:47:44| 0:000]{4}root@jhmac:~(127)# true ( 6)[Thu Sep 01 04:47:46| 0:000]{5}root@jhmac:~(✓)# ( 6)[Thu Sep 01 04:50:35| 0:000]{1}root@jhmac:~(✓)# exit logout ( 6)[Thu Sep 01 04:50:07| 0:000]{8}jhyland@jhmac:~(✓)$ ls -1 | head Applications BaseServer.py Desktop Documents Downloads Google Drive InventoryServer.py LDEV-342302 Library Movies'; 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