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"http:\/\/.*?\.pdf") test_str = ("omberg. Retrieved September 3, 2010.\n" "Jump up ^ Bloomberg August 4, 2010 article.\n" "Jump up ^ Lauerman, John (April 2, 2014). \"Apollo Falls as Education Department Demands Records\". Bloomberg News. Retrieved May 1, 2014.\n" "Jump up ^ \"Why Recent Criticism of the University of Phoenix is Unjustified, Rhonda P. Urban, Ementor, ezine by Warsaw School of Economics\". E-mentor.edu.pl. Retrieved September 3, 2010.\n" "Jump up ^ \"University of Phoenix 2007 Fact Book\". Phoenix.edu. Retrieved September 3, 2010.\n" "Jump up ^ \"U. of Phoenix Says Test Scores Vindicate Its Academic Model, Chronicle of Higher Education, BLUMENSTYK June 13, 2008\" (PDF). Upxnewsroom.com. Retrieved September 3, 2010.\n" "Jump up ^ \"University of Phoenix Ranks #1 in Graduating Master's Degree Students from Underrepresented Populations, Hispanic PR Wire\". Hispanicprwire.com. July 18, 2007. Retrieved September 3, 2010.\n" "Jump up ^ Nealy, Michael (August 20, 2009). \"Pride and Peril: Historically Black Colleges and Universities\". Diverse – Issues in Higher Education. Retrieved September 25, 2009.\n" "Jump up ^ Jennifer H. Svan. \"DOD renews contracts with four schools, drops University of Phoenix – News\". Stripes. Retrieved October 5, 2013.\n" "Jump up ^ University of Phoenix Faculty Overview. Retrieved February 17, 2008.\n" "Jump up ^ \"Supporting E-Learning at the University of Phoenix\" (PDF). Retrieved September 3, 2010.\n" "^ Jump up to: a b \"Faculty\". phoenix.edu.\n" "Jump up ^ \"Search Results\". Adjunct Project.\n" "Jump up ^ \"Howard Schmidt, Cybersecurity 'Czar': Who Is He?\". The Christian Science Monitor. Retrieved December 29, 2009.\n" "Jump up ^ Adams, Marilyn (February 5, 2008). \"Events, Drive Keep DOT Chief in the Spotlight\". USA Today. Retrieved September 3, 2010.http://somethink.pdf\n" "Jump up ^ \"Brad L. Dee\". Utah House of Representatives. Retrieved December 15, 2010.\n" "Jump up ^ United States Navy Biography U.S. Navy Web Site. Retrieved March 13, 2008.\n" "Jump up ^ \"Mayor Bill White Announces Police Chief Nominee\". City of Houston. February 27, http://RetrievedDecember.pdf 15, 2010.\n" "Jump up ^ \"Christina Brown\". MSNBC. 2010. Retrieved December 15, 2010.\n" "Jump up ^ The Big Executive? Shaq masters MBA MSNBC Web Site. Retrieved February 12, 2008.\n" "Jump up ^ Los Angeles Sparks Lisa Leslie Receives her Masters at University of Phoenix WireImage Website. Retrieved March 20, 2009.\n" "Jump up ^ \"Michael Russell completes undergrad program from University of Phoenix\". Tennisworldusa.org. January 15, 2012. Retrieved November 11, 2013.") match = regex.search(test_str) if match: print(f"Match 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