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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"^(((\*|(\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])))*$", flags=re.MULTILINE | re.IGNORECASE) test_str = ("* * * * * *\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 * * *") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html