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

/
/
msg

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 = "^((\\*)(\\/([0-5]?[0-9]))?|(([0-5]?[0-9])(\\/([0-5]?[0-9]))?(-([0-5]?[0-9]))?(,([0-5]?[0-9]))*))$"; final String string = "*\n" + "0\n" + "1\n" + "2\n" + "3\n" + "4\n" + "5\n" + "6\n" + "7\n" + "8\n" + "9\n" + "10\n" + "11\n" + "12\n" + "13\n" + "14\n" + "15\n" + "16\n" + "17\n" + "18\n" + "19\n" + "20\n" + "21\n" + "22\n" + "23\n" + "24\n" + "25\n" + "26\n" + "27\n" + "28\n" + "29\n" + "30\n" + "31\n" + "32\n" + "33\n" + "34\n" + "35\n" + "36\n" + "37\n" + "38\n" + "39\n" + "40\n" + "41\n" + "42\n" + "43\n" + "44\n" + "45\n" + "46\n" + "47\n" + "48\n" + "49\n" + "50\n" + "51\n" + "52\n" + "53\n" + "54\n" + "55\n" + "56\n" + "57\n" + "58\n" + "59\n" + "60\n" + "61\n" + "*/3\n" + "*/3/3\n" + "62\n" + "63\n" + "64\n" + "65\n" + "0/5\n" + "0/5/2\n" + "14,18\n" + "14,18,14,18,14,18\n" + "3-39\n" + "3-39-50\n" + "14,18,3-39,52"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.DOTALL); 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