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{10,21})|(\\+\\d{1,3}|\\d{1,4}|\\(\\+\\d{1,3}\\)|\\(\\d{1,2}\\))(([ -.]\\d+){1,5}$|([ -.]\\d+){1,5}([ -.](ext\\.|x|extention))[ -.]\\d{1,5}$)"; final String string = "Mexico (01) 55 1234 5678\n" + "Mexico (55) 1234 5678\n" + "Germany +49 30 2415889\n" + "UK +44 20 7930 7530\n" + "U.S.A. +1 503-225-5555\n" + "U.S.A. +1 503.225.5555\n" + "U.S.A. +001 503 225 5555\n" + "South Africa +27 21 419 3715\n" + "South Africa (+27) 21 419 3715\n" + "Japan +81 3-3211-3677\n" + "Japan +81 0112716677\n" + "Netherlands +31 20 610 9067\n" + "France +33 1 44 52 71 73\n" + "Australia +61 2 9669 3885\n" + "Australia (06) 1234 1234\n" + "Australia 0444 123 123\n" + "Spain +34 934 12 70 31\n" + "Spain 934 12 70 31\n" + "Portugal +351 21 846 1081\n\n" + "+81 3-3211-3677 ext. 12\n" + "+81 3-3211-3677 x 12\n" + "+81 3-3211-3677 extention 12\n" + "1231231233"; 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