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"(,+(.+[A-Z]{2} [0-9-]+)(,.*)(http.*[-._A-Za-z]+.[a-z]+),([-0-9]+),([- 0-9a-z]+))|(,+(.+[A-Z]{2} [0-9-]+))" test_str = (",P.O. Box 11000 Montgomery, AL 36191-0001 334-288-3900,,vvv\n\n" ",,15520 Rockfield Blvd. Ste. C Irvine, CA 92618-2792,...Whether you are looking for a list broker, list manager, database marketing or data processing profe*ssional, 's experienced...,http://www.carneydirect.com,949-581-5100,949-581-4564 fax,.,\n\n" ",115 Sansome Street San Francisco, CA 94104-4508,...We are a \"Results Agency\" based in San Francisco that is dedicated to producing top performing creative and strategy for...,http://www.creativelift.net,415-248-3174,415-398-0144 fax,.,\n\n" ",,2051 Dogwood Street Suite 220 Louisville, CO 80027,...The premier database marketing solutions provider and behavioral targeting firm for multi-channel marketers and advertisers. You can create, build and...,http://www.i-behavior.com,303-228-5000,303-...\n\n" ",198 Scribner Ave. Norwalk, CT 06854-1324,...I am an email marketing and direct marketing consultant. I help companies build, execute and analyze their customer acquisition...,http://www.reggiebrady.com,203-838-8138,.,,,,,,\n\n" ",RMI Direct Marketing,,44 Old Ridgebury Road, Plaza One Danbury, CT 06810-5129,...RMI is a premier customer acquisition, data and insert management firm. We specialize in market and competitor analysis, acquisition plans,...,http://www.rmidirect.com,203-798-0448,203-778-6130 fax,.,") 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