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

r"
"
gm

Test String

Substitution

Processing...

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"(.*),(\d+)-(\d+)-(\d+)" test_str = ("ocreedlandz,Olivia Creedland,F,40137 Northland Avenue,ocreedlandz@vinaora.com,1982-03-27\n" "ahogsden10,Aeriell Hogsden,M,46 Monica Parkway,ahogsden10@vistaprint.com,1954-03-04\n" "fharkins11,Forest Harkins,M,7489 Johnson Street,fharkins11@cpanel.net,2016-05-01\n" "rnerheny12,Raina Nerheny,F,29 Laurel Lane,rnerheny12@themeforest.net,1980-05-07\n" "msapp13,Marlo Sapp,F,30 Holmberg Lane,msapp13@live.com,1998-09-07\n" "bgripton14,Bunnie Gripton,M,21218 Dottie Drive,bgripton14@wired.com,1996-07-31\n" "jnazair15,Joanne Nazair,M,46 Sommers Crossing,jnazair15@senate.gov,2010-03-28\n" "rsummerbell16,Robenia Summerbell,F,5306 Armistice Hill,rsummerbell16@vinaora.com,2014-10-01\n" "dpowlesland17,Dannye Powlesland,F,45519 Steensland Circle,dpowlesland17@arstechnica.com,1952-06-23\n" "asherel18,Ania Sherel,M,57090 Johnson Way,asherel18@drupal.org,1963-12-18\n" "feliesco19,Fabien Eliesco,M,982 Portage Plaza,feliesco19@statcounter.com,1985-10-04\n" "jpoundford1a,Jan Poundford,M,24603 Loeprich Court,jpoundford1a@abc.net.au,1957-08-24\n" "rdrescher1b,Rosanna Drescher,F,3569 Glendale Point,rdrescher1b@marketwatch.com,1948-08-25\n" "xmarflitt1c,Ximenez Marflitt,M,688 Grover Drive,xmarflitt1c@soup.io,2012-11-17\n" "nshilston1d,Naomi Shilston,M,1 Summer Ridge Junction,nshilston1d@shop-pro.jp,1947-01-25\n" "ejina1e,Eddy Jina,M,6 Sycamore Drive,ejina1e@icq.com,1979-08-28\n" "dweild1f,Dorri Weild,F,128 Autumn Leaf Point,dweild1f@elpais.com,1980-03-31\n" "bhardes1g,Bryce Hardes,M,29458 Village Green Pass,bhardes1g@whitehouse.gov,1941-09-21\n" "adowtry1h,Andre Dowtry,F,81 Dunning Avenue,adowtry1h@slate.com,2018-04-27\n" "otiffany1i,Odelinda Tiffany,F,923 Atwood Court,otiffany1i@bizjournals.com,1992-12-19\n" "dcouzens1j,Dunstan Couzens,F,0 Main Crossing,dcouzens1j@patch.com,1990-09-25\n" "trolfi1k,Talyah Rolfi,M,746 Upham Hill,trolfi1k@buzzfeed.com,1942-08-22\n" "handerl1l,Hymie Anderl,F,5 3rd Crossing,handerl1l@indiegogo.com,1983-11-13\n" "delwill1m,Dorise Elwill,F,04 Monterey Road,delwill1m@ning.com,1996-10-03\n" "naberdalgy1n,Nehemiah Aberdalgy,M,3 Milwaukee Park,naberdalgy1n@fastcompany.com,2015-01-17\n" "lcorbally1o,Lawry Corbally,M,16934 Larry Crossing,lcorbally1o@biblegateway.com,2019-10-30\n" "groberson1p,Goldy Roberson,M,8 Walton Lane,groberson1p@chron.com,1986-08-20\n" "rtoland1q,Rosemonde Toland,F,40 Fisk Drive,rtoland1q@adobe.com,1981-12-03\n" "plethem1r,Parker Lethem,M,571 Vernon Parkway,plethem1r@tumblr.com,1940-10-19\n" "sgoundry1s,Salem Goundry,F,583 Saint Paul Crossing,sgoundry1s@army.mil,1959-07-16\n" "rmcconigal1t,Reggy McConigal,M,5663 Cambridge Way,rmcconigal1t@wikimedia.org,2007-10-27\n" "rdelue1u,Rochell Delue,M,9007 Hintze Park,rdelue1u@blogspot.com,1971-10-04\n" "aarnholz1v,Aeriela Arnholz,F,6 5th Drive,aarnholz1v@bandcamp.com,2011-08-06\n" "wmoraleda1w,Way Moraleda,M,07 Declaration Place,wmoraleda1w@washingtonpost.com,1973-02-25\n" "crisso1x,Caitrin Risso,F,99 Stuart Trail,crisso1x@sbwire.com,1946-10-21\n" "krawcliff1y,Kermy Rawcliff,M,2578 Lake View Center,krawcliff1y@w3.org,1943-05-28\n" "meykelbosch1z,Matthieu Eykelbosch,M,205 Tennessee Crossing,meykelbosch1z@jiathis.com,1979-09-03\n" "gmcilvaney20,Greer McIlvaney,M,0 Birchwood Trail,gmcilvaney20@aol.com,1953-05-26\n" "lmccullough21,Lucilia McCullough,M,72 Annamark Court,lmccullough21@ezinearticles.com,1975-09-05\n" "npead22,Nico Pead,M,2 Columbus Point,npead22@ezinearticles.com,2020-10-03\n" "agrigoliis23,Alma Grigoliis,M,091 Rigney Crossing,agrigoliis23@skype.com,1988-09-21\n" "bdobeson24,Basia Dobeson,M,7 Oneill Center,bdobeson24@delicious.com,2015-04-14\n" "owippermann25,Ortensia Wippermann,M,87610 Bashford Avenue,owippermann25@huffingtonpost.com,1984-01-08\n" "ghiggonet26,Geri Higgonet,F,66435 Russell Terrace,ghiggonet26@apple.com,2001-12-24\n" "sscorey27,Scotty Scorey,F,4798 Farragut Court,sscorey27@cbslocal.com,1978-09-21\n" "cjaukovic28,Cassandre Jaukovic,M,324 Little Fleur Point,cjaukovic28@netscape.com,1962-02-24\n" "ibrentnall29,Isac Brentnall,M,641 Raven Parkway,ibrentnall29@etsy.com,1999-07-27\n" "jlannin2a,Joela Lannin,M,5776 Melby Hill,jlannin2a@cdc.gov,1998-10-20\n" "dstudd2b,Doralynne Studd,M,8 Florence Way,dstudd2b@google.it,2007-01-16\n" "lhandyside2c,Livvy Handyside,M,55522 Daystar Center,lhandyside2c@europa.eu,1960-07-28\n" "lverne2d,La verne Stener,F,1 Manitowish Lane,lverne2d@msn.com,1943-05-16\n" "dbowgen2e,Danice Bowgen,M,3096 Kensington Hill,dbowgen2e@berkeley.edu,2015-01-06\n" "dmccutheon2f,Deirdre McCutheon,M,9074 Loeprich Road,dmccutheon2f@creativecommons.org,1967-06-11\n" "rcrauford2g,Raven Crauford,M,79787 Dryden Alley,rcrauford2g@hugedomains.com,1984-09-10\n" "msissland2h,Mercie Sissland,F,94 Loftsgordon Trail,msissland2h@ebay.com,1976-06-13\n" "nmccandie2i,Nedi McCandie,F,62844 Rigney Court,nmccandie2i@webs.com,2020-09-05\n" "iiley2j,Ignazio Iley,M,6816 Sommers Hill,iiley2j@over-blog.com,1945-08-26\n" "aghelerdini2k,Atalanta Ghelerdini,F,27 Mendota Center,aghelerdini2k@spotify.com,1976-09-15\n" "wbromehead2l,Waverly Bromehead,F,58 Killdeer Trail,wbromehead2l@tumblr.com,1977-07-09\n" "tkinch2m,Thaine Kinch,F,0151 Thackeray Point,tkinch2m@time.com,1946-03-12\n" "qrosone2n,Quinta Rosone,F,74582 Melby Way,qrosone2n@bigcartel.com,1965-03-01\n" "lcapron2o,Lucretia Capron,F,12510 Golden Leaf Hill,lcapron2o@cornell.edu,1979-12-26\n" "lreader2p,Lita Reader,F,240 Corry Circle,lreader2p@a8.net,1942-03-06\n" "khammelberg2q,Karita Hammelberg,F,8 Hazelcrest Crossing,khammelberg2q@geocities.com,1958-06-11\n" "bfontin2r,Brucie Fontin,F,21997 Charing Cross Point,bfontin2r@webnode.com,1973-11-03") subst = "\\1,\\4/\\3/\\2" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # 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