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

/
/
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{1,3}cm\\\\\""; final String string = "\"<?xml version=\\\"1.0\\\" standalone=\\\"no\\\"?>\",\n" + "\"<svg xmlns=\\\"http://www.w3.org/2000/svg\\\" version=\\\"1.1\\\" width=\\\"1250cm\\\" height=\\\"1250cm\\\">\",\n" + "\"<desc>9W43OV00W8JKMA1IJNEYAM1WTG9AZH8K10LC</desc>\",\n" + "\"<g id=\\\"HMLW03D1BYIQ\\\" fill=\\\"red\\\">\",\n" + "\"<rect x=\\\"252cm\\\" y=\\\"252cm\\\" width=\\\"252cm\\\" height=\\\"252cm\\\"/>\",\n" + "\"<rect x=\\\"72cm\\\" y=\\\"72cm\\\" width=\\\"72cm\\\" height=\\\"72cm\\\"/>\",\n" + "\"<rect x=\\\"131cm\\\" y=\\\"131cm\\\" width=\\\"131cm\\\" height=\\\"131cm\\\"/>\",\n" + "\"<rect x=\\\"228cm\\\" y=\\\"228cm\\\" width=\\\"228cm\\\" height=\\\"228cm\\\"/>\",\n" + "\"<rect x=\\\"240cm\\\" y=\\\"240cm\\\" width=\\\"240cm\\\" height=\\\"240cm\\\"/>\",\n" + "\"<rect x=\\\"232cm\\\" y=\\\"232cm\\\" width=\\\"232cm\\\" height=\\\"232cm\\\"/>\",\n" + "\"<rect x=\\\"192cm\\\" y=\\\"192cm\\\" width=\\\"192cm\\\" height=\\\"192cm\\\"/>\",\n" + "\"<rect x=\\\"0cm\\\" y=\\\"0cm\\\" width=\\\"0cm\\\" height=\\\"0cm\\\"/>\",\n" + "\"<rect x=\\\"0cm\\\" y=\\\"0cm\\\" width=\\\"0cm\\\" height=\\\"0cm\\\"/>\",\n" + "\"<rect x=\\\"0cm\\\" y=\\\"0cm\\\" width=\\\"0cm\\\" height=\\\"0cm\\\"/>\",\n" + "\"<rect x=\\\"65cm\\\" y=\\\"65cm\\\" width=\\\"65cm\\\" height=\\\"65cm\\\"/>\",\n" + "\"<rect x=\\\"81cm\\\" y=\\\"81cm\\\" width=\\\"81cm\\\" height=\\\"81cm\\\"/>\",\n" + "\"<rect x=\\\"65cm\\\" y=\\\"65cm\\\" width=\\\"65cm\\\" height=\\\"65cm\\\"/>\",\n" + "\"<rect x=\\\"80cm\\\" y=\\\"80cm\\\" width=\\\"80cm\\\" height=\\\"80cm\\\"/>\",\n" + "\"<rect x=\\\"82cm\\\" y=\\\"82cm\\\" width=\\\"82cm\\\" height=\\\"82cm\\\"/>\",\n" + "\"<rect x=\\\"81cm\\\" y=\\\"81cm\\\" width=\\\"81cm\\\" height=\\\"81cm\\\"/>\",\n" + "\"</g>\""; 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