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"name\s?[a-z]{0,2}\s([A-Z]{1}[a-z]+)" test_str = ("This is a spotted Lipitor Rumpelstiltskin named Alphred. He can't wait for the Turkey. 10/10 would pet really well https://t.co/6GUGO7azNX\n\n" "Sorry for the lack of posts today. I came home from school and had to spend quality time with my puppo. Her name is Zoey and she's 13/10 https://t.co/BArWupFAn0\n\n" "Ladies and gentlemen... I found Pipsy. He may have changed his name to Pablo, but he never changed his love for the sea. Pupgraded to 14/10 https://t.co/lVU5GyNFen\n\n" "HI. MY. NAME. IS. BOOMER. AND. I. WANT. TO. SAY. IT'S. H*CKIN. RIDICULOUS. THAT. DOGS. CAN'T VOTE. ABSOLUTE. CODSWALLUP. THANK. YOU. 13/10 https://t.co/SqKJPwbQ2g\n\n" "Name a more iconic quartet... I'll wait. 13/10 for all https://t.co/kCLgD8687T\n\n" "RT @dog_rates: This a Norwegian Pewterschmidt named Tickles. Ears for days. 12/10 I care deeply for Tickles https://t.co/0aDF62KVP7\n\n" "When bae calls your name from across the room. 12/10 (vid by @christinemcc98) https://t.co/xolcXA6gxe\n\n" "We normally don't rate bears but this one seems nice. Her name is Thea. Appears rather fluffy. 10/10 good bear https://t.co/fZc7MixeeT\n\n" "This pup's name is Sabertooth (parents must be cool). Ears for days. Jumps unannounced. 9/10 would pet diligently https://t.co/iazoiNUviP\n\n" "I would do radical things in the name of Dog God. I'd believe every word in that book. 10/10 https://t.co/9ZuGAmLZDR") 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