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"(.*)@user_(\S{8})([:| ])(.*)" test_str = ("USER_79321756 2010-03-03T04:15:26 ÜT: 47.528139,-122.197916 47.528139 -122.197916 RT @USER_2ff4faca: IF SHE DO IT 1 MORE TIME......IMA KNOCK HER DAMN KOOFIE OFF.....ON MY MOMMA&gt;&gt;haha. #cutthatout\n" "USER_79321756 2010-03-03T04:55:32 ÜT: 47.528139,-122.197916 47.528139 -122.197916 @USER_77a4822d @USER_2ff4faca okay:) lol. Saying ok to both of yall about to different things!:*\n" "USER_79321756 2010-03-03T05:13:34 ÜT: 47.528139,-122.197916 47.528139 -122.197916 RT @USER_5d4d777a: YOURE A FOR GETTING IN THE MIDDLE OF THIS @USER_ab059bdc WHO THE FUCK ARE YOU ? A FUCKING NOBODY !!!!&gt;&gt;Lol! Dayum! Aye!\n" "USER_79321756 2010-03-03T05:28:02 ÜT: 47.528139,-122.197916 47.528139 -122.197916 @USER_77a4822d yea ok..well answer that cheap as Sweden phone you came up on when I call.\n" "USER_79321756 2010-03-03T05:56:13 ÜT: 47.528139,-122.197916 47.528139 -122.197916 A sprite can disappear in her mouth - lil kim hmmmmm the can not the bottle right?") 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