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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"Reg: Email:", flags=re.MULTILINE) test_str = ("Hi,\n" "Congrats, your offer on a Ford Ka for the price of £2,000.00, was the winning offer!\n" " \n" "Car Details\n" " Ford Ka \n" "Model: Ford Ka\n" "Reg: LN61XVW\n" "Fee: £229.0\n" "Distance: 32 miles\n" "Mileage: 28709\n" "Car age: 13\n" "Colour: BLACK\n" "See customer details\n\n" "You’ll need to find a time that’s right for both parties so you can inspect the vehicle and make sure it looks as good as advertised.\n\n" "Ask us to collect for you or pick it up yourself and arrange payment with the seller.\n" " \n" "Customer Contact Details\n" " \n" "Name: Donna Irwin\n" "Phone: +447884015643\n" "Email: donna.irwin@btinternet.com\n" "Postcode: AL1 2ET\n" " \n" "Follow the link below to get in touch and exchange details.\n" "Contact the seller here\n" "Use the help link below if you have any questions.\n" " \n" " \n" "Happy Hunting,\n" "The Carwow Team") 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