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

r"
"
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = 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))" 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 = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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