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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(?:(?<!\d|\-|\+|\.)(?P<ch_a>[\u4e00-\u9fff]{2})?(?P<Hours>[0-2]?\d)(?:[:\.时時]| ?h ?)(?P<Minutes>[0-5]\d(?!\d))\:?(?:(?:[:\.分]| ?m ?)(?P<Seconds>[0-5]\d(?!\d)))?秒?(?:[,\.](?P<SecodsFraction>\d{9}|\d{6}|\d{3}(?!\d)))?(?:\ \w\W)?(?:[\.\s]?(?:(?P<Z>(?:[a-zA-Z]{3,5}|Z|\[\w+\/\w+\])|(?:[+-]\d\d?\:?[0,3,4]?[0,5]?))|(?P<a>[dapmDAPM]{2})))*(?!\S))", flags=re.MULTILINE) test_str = ("19990322+0100\n" "19990322\n" "1999-03-22 AD\n" "1999-03-22+01:00\n" "1999-03-22T05:06:07.000[Europe/Paris]\n" "1999-03-22T05:06:07.000\n" "1999-03-22T05:06:07\n" "1999-03-22T05:06:07.000Z\n" "1999-03-22T05:06:07.000+01:00\n" "1999-03-22T05:06:07+01:00\n" "1999-081+01:00\n" "1999W132\n" "1999-W13-2\n" "1999-03-22T05:06:07.000+01:00[Europe/Paris]\n" "1999-03-22T05:06:07+01:00[Europe/Paris]\n" "22.3.99\n" "22.3.99 5.06\n" "22.3.1999 5.06.07\n" "22.3.1999 5:06:07\n" "22-03-99\n" "22-03-99 05:06\n" "22-03-1999 05:06:07\n" "22.03.99\n" "22. März 1999\n" "Montag, 22. März 1999\n" "22.03.1999\n" "22.03.99 05:06\n" "22. März 1999 05:06:07 MEZ\n" "22.03.1999 05:06:07\n" "22.03.99 05:06:07\n" "22.03.1999 05:06\n" "Montag, 22. März 1999 05:06 Uhr MEZ\n" "22-Mar-1999\n" "22/03/99 5:06 AM\n" "Monday, March 22, 1999 5:06:07 o'clock AM CET\n" "22-Mar-1999 5:06:07 AM\n" "22 March 1999\n" "Monday, 22 March 1999\n" "22-Mar-1999\n" "22 March 1999 05:06:07 CET\n" "Monday, 22 March 1999 05:06:07 o'clock CET\n" "22-Mar-1999 05:06:07\n" "22-Mar-99 05.06.07.000000888 AM\n" "3/22/99\n" "03/11/22\n" "03-22-99\n" "3-22-99\n" "Mar 22, 1999\n" "March 22, 1999\n" "Monday, March 22, 1999\n" "Mar 22 1999\n" "March 22 1999\n" "03-22-1999\n" "3-22-1999\n" "1999-03-22+01:00\n" "22/03/1999\n" "22/3/1999\n" "03/22/1999\n" "3/22/1999\n" "1999/3/22\n" "3/22/99 5:06 AM\n" "03/22/99 5:06 AM\n" "03-22-99 5:06 AM\n" "3-22-99 5:06 AM\n" "Mar 22, 1999 5:06:07 AM\n" "Monday, March 22, 1999 5:06:07 AM CET\n" "Mon Mar 22 05:06:07 CET 1999\n" "Mon, 22 Mar 1999 05:06:07 +0100\n" "22 Mar 1999 05:06:07 +0100\n" "03-22-1999 5:06:07 AM\n" "3-22-1999 5:06:07 AM\n" "1999-03-22 5:06:07 AM\n" "1999-3-22 5:06:07 AM\n" "1999-03-22 05:06:07.0\n" "22/03/1999 5:06:07 AM\n" "22/3/1999 5:06:07 AM\n" "03/22/1999 5:06:07 AM\n" "3/22/1999 5:06:07 AM\n" "03/22/99 5:06:07 AM\n" "03/22/99 5:06:07\n" "3/22/99 5:06:07\n" "22/03/1999 5:06 AM\n" "22/3/1999 5:06 AM\n" "03/22/1999 5:06 AM\n" "3/22/1999 5:06 AM\n" "03-22-99 5:06:07 AM\n" "3-22-99 5:06:07 AM\n" "03-22-1999 5:06 AM\n" "3-22-1999 5:06 AM\n" "1999-03-22 5:06 AM\n" "1999-3-22 5:06 AM\n" "Mar.22.1999\n" "22/Mar/1999 5:06:07 +0100\n" "22/Mar/99 5:06 AM\n" "22/03/99\n" "22/03/99 5:06\n" "22.3.99 5:06\n" "22.03.99\n" "22.03.1999\n" "22.03.99 5:06\n" "22.03.1999 5:06:07\n" "22.3.1999\n" "22.3.1999 5:06\n" "99-03-22\n" "1999-03-22\n" "22 mars 1999 05:06:07 CET\n" "March 22, 1999 5:06:07 CET AM\n" "1999-03-22 05:06:07\n" "lundi 22 mars 1999 5 h 06 CET\n" "22/03/99\n" "22 mars 1999\n" "22 mars 1999\n" "lundi 22 mars 1999\n" "22/03/99 05:06\n" "03/22/99 05:06\n" "3/22/99 05:06\n" "03-22-99 05:06\n" "3-22-99 05:06\n" "22 mars 1999 05:06:07\n" "22 mars 1999 05:06:07 CET\n" "03-22-1999 05:06:07\n" "3-22-1999 05:06:07\n" "1999-3-22 05:06:07\n" "22/03/1999 05:06:07\n" "22/3/1999 05:06:07\n" "03/22/1999 05:06:07\n" "3/22/1999 05:06:07\n" "lundi 22 mars 1999 05 h 06 CET\n" "22/03/99 05:06:07\n" "03/22/99 05:06:07\n" "3/22/99 05:06:07\n" "22/03/1999 05:06\n" "22/3/1999 05:06\n" "03/22/1999 05:06\n" "3/22/1999 05:06\n" "03-22-99 05:06:07\n" "3-22-99 05:06:07\n" "03-22-1999 05:06\n" "3-22-1999 05:06\n" "1999-3-22 05:06\n" "99/03/22 05:06\n" "1999.03.22\n" "1999.03.22 05:06:07\n" "1999.03.22 05:06\n" "1999.03.22.\n" "1999.03.22. 5:06:07\n" "1999.03.22. 5:06\n" "22.3.1999 05:06:07\n" "22.3.1999 05:06\n" "22-mar-1999\n" "22/03/99 5.06\n" "99-03-22 05:06\n" "22-mar-1999 5.06.07\n" "22 marzo 1999 5.06.07 CET\n" "lunedì 22 marzo 1999 5.06.07 CET\n" "05:06 22/03/99\n" "05:06:07 22/03/1999\n" "99/03/22\n" "1999/03/22\n" "99/03/22 5:06\n" "03/22/99 5:06\n" "3/22/99 5:06\n" "03-22-99 5:06\n" "3-22-99 5:06 AM\n" "03-22-1999 5:06:07\n" "3-22-1999 5:06:07\n" "1999-03-22 5:06:07\n" "99/03/22 5:06:07\n" "3/22/99 5:06:07 AM\n" "1999/03/22 5:06\n" "22/03/1999 5:06\n" "22/3/1999 5:06\n" "03/22/1999 5:06\n" "3/22/1999 5:06\n" "03-22-99 5:06:07\n" "3-22-99 5:06:07\n" "03-22-1999 5:06\n" "3-22-1999 5:06\n" "1999-03-22 5:06\n" "1999-3-22 5:06\n" "99. 3. 22\n" "1999. 3. 22\n" "99.3.22\n" "99.3.22 05.06\n" "1999-03-22 05.06.07\n" "99.22.3\n" "1999.22.3\n" "99.22.3 05:06\n" "1999.22.3 05:06:07\n" "22.3.99 05:06\n" "22.3.1999 05:06:\n" "22-3-99\n" "22-3-99 5:06\n" "22-03-1999\n" "22-03-1999 5:06\n" "22.03.99 5:06\n" "22.03.1999 5:06:07\n" "1999-03-22 5:06:07.PD\n" "99-03-22 5.06.PD\n" "1999-03-22 5.06.07.PD CET\n" "22.3.99.\n" "22.03.1999.\n" "22.3.99. 05.06\n" "22.03.1999. 05.06.07\n" "22.03.1999. 05.06.07 CET\n" "05:06:07 22-03-1999\n" "05:06 22/03/1999\n" "99-3-22\n" "1999-3-22\n" "1999年3月22日\n" "1999年3月22日 星期一\n" "99-3-22 上午5:06\n" "1999-3-22 5:06:07\n" "1999年3月22日 上午05时06分07秒\n" "1999年3月22日 5時06分07秒 CET\n" "1999年3月22日 星期一 上午05时06分07秒 CET\n") 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