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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?<=m)(2|3)"; final String string = "superscript\n" + "(?<=m)(2|3)\n" + "®|™\n" + "(?<=\\d)(de|ème)\n" + "REF\n" + "\\d{6}/(D|T|X)\n" + "REF2\n" + "\\d{3}/(D|T|X)\n" + "REF3\n" + "\\d{6}(?-)\n" + "VET\n" + "garantie[^\\r\\n]+jaar\n" + "Fraction\n" + "\\b1/2\\b\n\n" + "PARQUET STRATIFIE ‘MEGALOFT’\n" + "Différents motifs \n" + "Longueur 1286mm x largeur \n" + "194mm \n" + "10000kcal/u\n" + "25mm2\n" + "10dm3 10dm3/u\n" + "1000m3/u\n" + "850l/u\n" + "1000m3/h\n" + "850l/h\n" + "1,99m2/pak\n" + "1,33m3\n" + "1,25m2\n" + "25kg \n" + "700559/D\n" + "1,59m3/pak\n" + "1,996m2/paquet\n" + "700496-123566-123/D\n" + "1,996m2/paquet\n" + "123566-123/D\n" + "1,99m2 en 199m3/h\n" + "135234-123/D\n\n\n" + "Gerst 004729/D\n" + "Schors 058157/D\n" + "Ø 30/60 x H230cm\n" + "Polyester doek 280gr/m2\n" + "Crossover®-ontstekingssysteem\n" + "™ Toelatingsnr: 3001B\n" + "32/38mm slang\n" + "ZANDFILTERKIT 10m3/u\n" + "Debiet 1,2m2/u\n" + "Zinklaag: 180-250gr/m2\n" + "2de handgreep\n" + "2ème poignon\n" + "Garantie 25 jaar\n" + "10 jaar waarborg\n" + "Maaihoogteregeling 20-75mm\n\n\n" + "Gerst 004729/D\n" + "Schors 058157/D\n" + "Ø 30/60 x H230cm\n" + "Polyester doek 280gr/m2\n" + "Crossover®-ontstekingssysteem\n" + "™ Toelatingsnr: 3001B\n" + "32/38mm slang\n" + "ZANDFILTERKIT 10m3/u\n" + "Debiet 1,2m2/u\n" + "Zinklaag: 180-250gr/m2\n" + "2de handgreep\n" + "2ème poignon\n" + "garantie 25 jaar\n" + "garantie 25 jaar\n" + "Garantie 25 ans jar\n" + "Jaar Garantie 25 \n" + "25 jaar garantie\n" + "10 jaar waarborg\n" + "Maaihoogteregeling 20-75mm\n" + "1/2\n" + "®\n" + "541358/9/60\n" + "541358-12-12/D\n" + "541358-123-123/D\n" + "541358-1234-1234/D\n" + "541358-12345-12345/D\n" + "541358-123456-123456/D"; final Pattern pattern = Pattern.compile(regex); 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