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

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/(\d+\.)\s+([\w\-#]+)\s+(\{[^\}]+\})\s+\1\.+\s+([\w\-#]+)\s+(\{[^\}]+\})/m'; $str = '[Event "Live Chess"] [Site "Chess.com"] [Date "2018.12.07"] [Round "-"] [White "Joerg64"] [Black "Damir_Khamzin"] [Result "0-1"] [WhiteElo "1317"] [BlackElo "1312"] [TimeControl "1800"] [EndTime "9:36:56 PST"] [Termination "Damir_Khamzin поставил мат"] 1. d4 {[%clk 0:29:59.9]} 1... d5 {[%clk 0:29:57.6]} 2. c4 {[%clk 0:29:50.5]} 2... e6 {[%clk 0:29:52.9]} 3. a3 {[%clk 0:29:46.5]} 3... h6 {[%clk 0:29:27.5]} 4. Nc3 {[%clk 0:29:44.3]} 4... Nf6 {[%clk 0:29:24.7]} 5. h3 {[%clk 0:29:41.2]} 5... Nbd7 {[%clk 0:29:07.7]} 6. Nf3 {[%clk 0:29:23.2]} 6... Be7 {[%clk 0:28:59]} 7. e3 {[%clk 0:29:17.7]} 7... b6 {[%clk 0:28:49.7]} 8. Bd3 {[%clk 0:29:05.4]} 8... Bb7 {[%clk 0:28:39]} 9. b4 {[%clk 0:28:29.3]} 9... c5 {[%clk 0:28:01.5]} 10. b5 {[%clk 0:28:18.5]} 10... dxc4 {[%clk 0:27:46.4]} 11. Bxc4 {[%clk 0:28:15.2]} 11... cxd4 {[%clk 0:27:38]} 12. exd4 {[%clk 0:27:57.6]} 12... O-O {[%clk 0:27:28.5]} 13. O-O {[%clk 0:27:54.6]} 13... Qc7 {[%clk 0:27:05.4]} 14. Re1 {[%clk 0:26:46.2]} 14... Qxc4 {[%clk 0:26:28.7]} 15. Ne5 {[%clk 0:26:11.3]} 15... Qxc3 {[%clk 0:26:04.9]} 16. Bf4 {[%clk 0:25:46.4]} 16... Nxe5 {[%clk 0:25:52.3]} 17. dxe5 {[%clk 0:25:38.1]} 17... Nd5 {[%clk 0:25:40.1]} 18. Bh2 {[%clk 0:25:27.6]} 18... Bxa3 {[%clk 0:24:33]} 19. Rb1 {[%clk 0:24:42.4]} 19... Bc5 {[%clk 0:24:13.6]} 20. Re2 {[%clk 0:24:27.9]} 20... Qd4 {[%clk 0:22:45.6]} 21. Rd2 {[%clk 0:24:21.1]} 21... Qh4 {[%clk 0:22:39.6]} 22. Bg3 {[%clk 0:24:14.8]} 22... Qe7 {[%clk 0:22:35.3]} 23. Rc2 {[%clk 0:20:18.6]} 23... Rad8 {[%clk 0:21:55]} 24. Qg4 {[%clk 0:20:10.7]} 24... Qg5 {[%clk 0:21:18.3]} 25. Qa4 {[%clk 0:19:52.9]} 25... Qg6 {[%clk 0:20:48.8]} 26. Kh1 {[%clk 0:19:22.1]} 26... Nb4 {[%clk 0:20:21.5]} 27. Rcb2 {[%clk 0:18:39.8]} 27... Ra8 {[%clk 0:19:41.5]} 28. Rxb4 {[%clk 0:18:22.8]} 28... Bxb4 {[%clk 0:19:38.6]} 29. Qxb4 {[%clk 0:18:14.3]} 29... Qe4 {[%clk 0:19:22.3]} 30. Qb2 {[%clk 0:17:43.9]} 30... Qxg2# {[%clk 0:19:15.9]} 0-1 '; $subst = "\n\1 \2 \4 \3 - \5"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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