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

/
/
gmi

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?))(\\/\\d\\d?)?)|(\\d\\d?\\-\\d\\d?))(,(((\\*|(\\d\\d?))(\\/\\d\\d?)?)|(\\d\\d?\\-\\d\\d?)))*\\s(((\\*|(\\d\\d?))(\\/\\d\\d?)?)|(\\d\\d?\\-\\d\\d?))(,(((\\*|(\\d\\d?))(\\/\\d\\d?)?)|(\\d\\d?\\-\\d\\d?)))*\\s(((\\*|(\\d\\d?))(\\/\\d\\d?)?)|(\\d\\d?\\-\\d\\d?))(,(((\\*|(\\d\\d?))(\\/\\d\\d?)?)|(\\d\\d?\\-\\d\\d?)))*\\s(\\?|(((\\*|(\\d\\d?L?))(\\/\\d\\d?)?)|(\\d\\d?L?\\-\\d\\d?L?)|L|(\\d\\d?W))(,(((\\*|(\\d\\d?L?))(\\/\\d\\d?)?)|(\\d\\d?L?\\-\\d\\d?L?)|L|(\\d\\d?W)))*)\\s(((\\*|(\\d|10|11|12|JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))(\\/\\d\\d?)?)|((\\d|10|11|12|JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)\\-(\\d|10|11|12|JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)))(,(((\\*|(\\d|10|11|12|JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))(\\/\\d\\d?)?)|((\\d|10|11|12|JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)\\-(\\d|10|11|12|JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))))*\\s(((\\*|([0-7]|MON|TUE|WED|THU|FRI|SAT|SUN)L?)(\\/\\d\\d?)?)|(([0-7]|MON|TUE|WED|THU|FRI|SAT|SUN)L?\\-([0-7]|MON|TUE|WED|THU|FRI|SAT|SUN)L?)|([0-7]|MON|TUE|WED|THU|FRI|SAT|SUN)L?#([1-5]))(,(((\\*|([0-7]|MON|TUE|WED|THU|FRI|SAT|SUN)L?)(\\/\\d\\d?)?)|(([0-7]|MON|TUE|WED|THU|FRI|SAT|SUN)L?\\-([0-7]|MON|TUE|WED|THU|FRI|SAT|SUN)L?)|([0-7]|MON|TUE|WED|THU|FRI|SAT|SUN)L?#([1-5])))*$"; final String string = "* * * * * *\n" + "* * * * * *\n" + "* * * * * *\n" + "3 * * * * *\n" + "3 * * * * *\n" + "3 * * * * *\n" + "3 * * * * *\n" + "3 * * * * *\n" + "5/15 * * * * *\n" + "5/15 * * * * *\n" + "5/15 * * * * *\n" + "5/15 * * * * *\n" + "5/15 * * * * *\n" + "7,19 * * * * *\n" + "7,19 * * * * *\n" + "7,19 * * * * *\n" + "2-45 * * * * *\n" + "2-4 * * * * *\n" + "42-45 * * * * *\n" + "42-45 * * * * *\n" + "42-45 * * * * *\n" + "42-45 * * * * *\n" + "42-63 * * * * *\n" + "0 3 * * * *\n" + "0 3 * * * *\n" + "0 0/15 * * * *\n" + "0 0/15 * * * *\n" + "0 0/15 * * * *\n" + "0 0/15 * * * *\n" + "0 7,19 * * * *\n" + "0 7,19 * * * *\n" + "0 * 3 * * *\n" + "0 * 3 * * *\n" + "0 * 3 * * *\n" + "0 * 0/15 * * *\n" + "0 * 0/15 * * *\n" + "0 * 0/15 * * *\n" + "0 * 0/15 * * *\n" + "0 * 0/15 * * *\n" + "0 * 7,19 * * *\n" + "0 * 7,19 * * *\n" + "0 * 7,19 * * *\n" + "0 1 * * * *\n" + "0 0 * * * *\n" + "0 * * 3 * *\n" + "0 * * 3 * *\n" + "0 * * 3 * *\n" + "0 * * 3 * *\n" + "0 0 0 1/15 * *\n" + "0 0 0 1/15 * *\n" + "0 0 0 1/15 * *\n" + "0 0 0 1/15 * *\n" + "0 0 0 7,19 * *\n" + "0 0 0 7,19 * *\n" + "0 0 0 7,19 * *\n" + "0 0 0 7,19 * *\n" + "0 0 0 L * *\n" + "0 0 0 L * *\n" + "0 0 0 3L * *\n" + "0 0 0 3L * *\n" + "0 0 0 9W * *\n" + "0 0 0 9W * *\n" + "0 0 0 9W * *\n" + "0 0 0 9W * *\n" + "0 0 0 9X */2 *\n" + "0 0 0 9#2 * *\n" + "0 0 0 1 5 *\n" + "0 0 0 1 5/2 *\n" + "0 0 0 1 5/2 *\n" + "0 0 0 1 5/10 *\n" + "0 0 0 1 3,7,12 *\n" + "0 0 0 1 3,7,12 *\n" + "0 0 0 1 3,7,12 *\n" + "0 0 0 1 MAR,JUL,DEC *\n" + "0 0 0 1 MAR,JUL,DEC *\n" + "0 0 0 1 MAR,JUL,DEC *\n" + "0 0 0 1 ? *\n" + "0 0 0 * * 3\n" + "0 0 0 * * 3\n" + "0 0 0 * * 3\n" + "0 0 0 * * 3\n" + "0 0 0 * * 3/2\n" + "0 0 0 * * 3/2\n" + "0 0 0 * * 3/2\n" + "0 0 0 * * 3/2\n" + "0 0 0 * * 1,5,7\n" + "0 0 0 * * 1,5,7\n" + "0 0 0 * * 1,5,7\n" + "0 0 0 * * MON,FRI,SUN\n" + "0 0 0 * * MON,FRI,SUN\n" + "0 0 0 * * MON,FRI,SUN\n" + "0 0 0 * * 5L\n" + "0 0 0 * * 5L\n" + "0 0 0 * * 5L\n" + "0 0 0 * * FRIL\n" + "0 0 0 * * 5W\n" + "0 0 0 * * 5?3\n" + "0 0 0 * * 0\n" + "0 0 0 * * 0L\n" + "0 0 0 * * 0#2\n" + "0 0 0 * * 7\n" + "0 0 0 * * 7L\n" + "0 0 0 * * 7#2\n" + "0 0 0 * * 5#3\n" + "0 0 0 * * 5#3\n" + "0 0 0 * * 7#1\n" + "0 0 0 * * 7#1\n" + "0 0 0 * * 3#5\n" + "0 0 0 * * WED#5\n" + "* * 5-1 * * *"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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