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

/
/
gmi

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"^(?:ach\sdebit\s|point\sof\ssale\sdebit\s)?(?:l\d{3}\s)?(?:TIME\s\d\d:\d\d\s[A|P]M\s*)?(?:DATE\s\d\d-\d\d\s)?([a-z-*'\s]+)(?:[\d\s]{15,}|\d{3}-?\d{3}-?\d{4}|#\w+)?" test_str = ("ACH Debit 5/3 MORTGAGE LN PAYMENT 017136000924355\n" "Point of Sale Debit L340 TIME 08:37 AM DATE 04-26 JR GENERAL STORE CHARLOTTE NC\n" "Point of Sale Debit L343 TIME 07:02 PM DATE 04-25 AUTOZONE 4982 35CONCORD NC\n" "Point of Sale Debit L343 TIME 07:00 PM DATE 04-25 AUTOZONE 4982 35CONCORD NC\n" "Point of Sale Debit L340 DATE 04-25 ASF*ATA KARATE OF 800-5258967\n" "ACH Debit GS Home Imp Fin 8669360602 017116001434401\n" "Point of Sale Debit L343 TIME 07:56 AM DATE 04-27 AUTOZONE 4982 35CONCORD NC\n" "Point of Sale Debit L340 DATE 04-25 CHICK-FIL-A #01118CONCORD\n" "Point of Sale Debit L340 DATE 04-26 ANGELAS CONCORD\n" "Point of Sale Debit L340 DATE 04-25 ATA KARATE CONCORDCONCORD\n" "Check INCLEARING CHECK\n" "Point of Sale Debit L341 TIME 03:52 PM DATE 04-27 HARRIS TE 358 GEOCONCORD NC\n" "Point of Sale Debit L341 TIME 08:57 AM DATE 04-28 WALGREENS STORE 1CHARLOTTE NC\n" "Point of Sale Debit L340 DATE 04-26 CHICK-FIL-A #01118CONCORD\n" "Point of Sale Debit L340 DATE 04-27 HT EXPRESS LANE #6CONCORD\n\n") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE) 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