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

/
/
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"Køretøjsliste for \d{7} for dato \d{2}.\d{2}.\d{4} - \d{2}.\d{2}.\d{4}.xls" test_str = ("Køretøjsliste for 4874349 for dato 31.01.2020 - 01.05.2020.xls\n" "Køretøjsliste for 4874351 for dato 30.02.2021 - 03.10.2021.xls\n" "Køretøjsliste for 4874352 for dato 29.03.2022 - 09.06.2022.xls\n" "Køretøjsliste for 4874353 for dato 28.04.2022 - 11.09.2022.xls\n" "Køretøjsliste for 4874354 for dato 27.05.2022 - 15.12.2022.xls\n" "Køretøjsliste for 4874355 for dato 26.06.2023 - 22.07.2023.xls\n" "Køretøjsliste for 4874356 for dato 25.07.2022 - 27.08.2022.xls\n" "Køretøjsliste for 4874357 for dato 24.09.2029 - 28.12.2029.xls\n" "Køretøjsliste for 4874358 for dato 11.10.2015 - 29.10.2015.xls\n" "Køretøjsliste for 4874359 for dato 04.11.2024 - 30.11.2025.xls\n" "Køretøjsliste for 4874360 for dato 01.12.2028 - 31.12.2029.xls") 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