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"\d{1,3}\.\s[a-zA-Z\d\?\.\s].+$\n\s(a?\)\s[a-zA-Z].+).+\n\s(b?\)\s[A-Za-z].+).+\n\s(c\).[a-zA-Z].+)", flags=re.MULTILINE) test_str = ("617. What would you like to eat for lunch? …, I don’t mind.\n" " a) Nothing\n" " b) Anything\n" " c) Something\n" "618. Where do you want to go on holiday? … with a beach.\n" " a) Somewhere\n" " b) Nowhere\n" "613. You look familiar. Haven’t I seen you … before?\n" " a) nowhere\n" " b) anywhere\n" " c) somewhere\n" "614. She left the room without saying … .\n" " a) nothing\n" " b) anything\n" " c) everything\n" "615. I have never been … more beautiful than Thailand.\n" " a) somewhere\n" " b) nowhere\n" " c) anywhere\n" "616. Who was at the party? …, so something very bad must have happened.\n" " a) No one\n" " b) Anyone\n" " c) Everyone\n" "617. What would you like to eat for lunch? …, I don’t mind.\n" " a) Nothing\n" " b) Anything\n" " c) Something\n" "618. Where do you want to go on holiday? … with a beach.\n" " a) Somewhere\n" " b) Nowhere\n" " c) Anywhere\n" "619. I have … to say to you. Goodbye!\n" " a) nothing\n" " b) everything\n" " c) something\n" "620. I felt so good being on stage. I was sure that … was looking at me.\n" " a) someone\n" " b) everyone\n" " c) no one\n" "621. Can you please … some money until next week?\n" " a) lend \n" " b) borrow\n" " c) give\n" "622. I decided to invest in the commodities as the … on offer from bank was extremely low.\n" " a) tax \n" " b) rent \n" " c) interest\n" "623. Many retailers refuse to exchange purchases unless you can show them your … .\n" " a) receipt\n" " b) bill\n" " c) Anywhere\n" "619. I have … to say to you. Goodbye!\n" " a) nothing") 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