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"[X]*\d{4}\ [A-Z]*$", flags=re.MULTILINE) test_str = ("Aokia How doers\n" "getmore done.\n" "9615 DIAMOND CENTER DRIVE\n" "MENTOR, OH 44060 (440)357-0428\n" "3815 00061 42905 05/01/22 01:57PM\n" "SALE SELF CHECKOUT\n" "037155808113 DRAIN CRT <A> 15.88\n" "CHROME FINISH PLASTIC TUB STOPPER\n" "SUBTOTAL 15.88\n" "SALES TAX 1.15\n" "TOTAL $17.03\n" "XXXXXXXXXXXX4651 DEBIT\n" "USD$17.03\n" "AUTH CODE 001059\n" "Chip Read Verified By PIN\n" "AID A0000000042203 US Debit\n" "3815 05/01/22 01:57 PM\n" "3815 61 42905 05/01/2022 9250\n" "RETURN POLICY DEFINITIONS\n" "POLICY ID DAYS POLICY EXPIRES ON\n" "A 1 90 07/30/2022\n" "****\n" "DID WE NAIL IT?\n" "Take a short survey for a chance TO WIN\n" "A$5,000 HOME DEPOT GIFT CARD\n" "Opine en español\n" "www.homedepot.com/survey\n" "User ID: H88 89914 86160\n" "PASSWORD: 22251 86099\n" "Entries must be completed within 14 days\n" "of purchase. Entrants must be 18 or\n" "older to enter. See complete rules on\n" "website. No purchase necessary.") 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