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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "\\d-\\d"; final String string = "Hallo1-2\n" + "1. c4 e5 2. e3 c5 3. Nc3 Nc6 4. g3 f5 5. d3 Nf6 6. Bg2 d6\n" + "7. Nh3 Be6 8. Nd5 Bxd5 9. cxd5 Ne7 10. e4 h6 11. f4 Qc7\n" + "12. O-O g6 13. Bd2 Bg7 14. fxe5 dxe5 15. Rc1 Qd6 16.a3 O-O\n" + "17. Rc2 Rac8 18. b4 b6 19. Qc1 Kh7 20. bxc5 Rxc5 21. Bb4 Rxc2\n" + "22. Bxd6 Rxc1 23. Rxc1 Re8 24. Nf2 Nc8 25. Bxe5 Rxe5 26. Rxc8\n" + "Re7 27. Kf1 Ne8 28. Rc6 Rd7 29. Nh3 Nd6 30. a4 Be5 31. Nf4\n" + "fxe4 32. dxe4 Rf7 33. Ke2 Bxf4 34. gxf4 Nb7 35. e5 Nc5 36. e6\n" + "Re7 37. Bh3 Re8 38. Rc7+ Kg8 39. Rxa7 Kf8{ 40. Rf7+ Kg8 41. f5\n" + "Ne4 42. Bg2 Nd6 43. fxg6 Rc8 44. Rd7 {Rc2+ 45. Kd3 { The {Chess\n" + "Player 1851, p. 58} 1-0 F.B.I. I.R.S.} asdf CIA} 123 12345 123456 1234567 412-555-1212 a as ape d1/2-1/2 bug O-O 12345 The ape was at the apex \n\n\n\n" + "Commands:\n" + "\\{+\\w+ {+Wort ; z.B. {Chess\n" + "\\d+\\d.\n" + "\\d-\\d Zahl - Zahl; z.B. 1-1\n" + "\\d+\\. Zahl + Punkt ; z.B. 4.\n" + "(\\d\\..)\n" + "[[:digit:]]+[.]\n" + "(ape[^ ]?)\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html