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

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"\ {0,1}([A-Za-z]*)\t([0-9]*)" test_str = ("74572: Blaufelden\n" " Alkertshausen\n" " Billingsbach\n" " Blaubach\n" " Blaufelden\n" " Brüchlingen\n" " Ehringshausen\n" " Emmertsbühl\n" " Engelhardshausen\n" " Erpfersweiler\n" " Gammesfeld\n" " Herrentierbach\n" " Heufelwinden\n" " Kottmannsweiler\n" " Lentersweiler\n" " Metzholz\n" " Mittelbach\n" " Naicha\n" " Niederweiler\n" " Raboldshausen\n" " Saalbach\n" " Simmetshausen\n" " Wiesenbach\n" " Wittenweiler\n\n" "74575: Schrozberg\n" " Bartenstein\n" " Böhmweiler\n" " Bossendorf\n" " Bovenzenweiler\n" " Eichholz\n" " Eichswiesen\n" " Enzenweiler\n" " Ettenhausen\n" " Funkstatt\n" " Ganertshausen\n" " Gemmhagen\n" " Großbärenweiler\n" " Gütbach\n" " Hechelein\n" " Heiligenbronn\n" " Heuchlingen\n" " Hirschbronn\n" " Hornungshof\n" " Hummertsweiler\n" " Kälberbach\n" " Kleinbärenweiler\n" " Klopfhof\n" " Könbronn\n" " Krailshausen\n" " Kreuzfeld\n" " Leuzendorf\n" " Lindlein\n" " Mäusberg\n" " Obereichenrot\n" " Reichertswiesen\n" " Reupoldsrot\n" " Riedbach\n" " Schmalfelden\n" " Schrozberg\n" " Sigisweiler\n" " Speckheim\n" " Spielbach\n" " Spindelbach\n" " Standorf\n" " Untereichenrot\n" " Wittmersklingen\n" " Wolfskreut\n" " Zell\n\n" "74585: Rot am See\n" " Beimbach\n" " Bemberg\n" " Brettenfeld\n" " Brettheim\n" " Hausen\n" " Hegenau\n" " Herbertshausen\n" " Heroldhausen\n" " Hertershofen\n" " Hilgartshausen\n" " Kleinansbach\n" " Kleinbrettheim\n" " Kühnhard\n" " Lenkerstetten\n" " Musdorf\n" " Niederwinden\n" " Oberndorf\n" " Oberwinden\n" " Reinsbürg\n" " Reubach\n" " Rot am See\n" " Weikersholz\n\n" "74599: Wallhausen\n" " Asbach\n" " Hengstfeld\n" " Limbach\n" " Michelbach an der Lücke\n" " Roßbürg\n" " Schainbach\n" " Schönbronn\n" " Wallhausen\n\n" "91471: Illesheim\n" " Illesheim 91471\n" " Sontheim 91471\n" " Urfersheim 91471\n" " Westheim 91471\n\n" "91541: Rothenburg\n" " Bettenfeld\n" " Burgstall\n" " Detwang\n" " Dürrenhof\n" " Hemmendorf ob der Tauber\n" " Herrnwinden\n" " Leuzenbronn ob der Tauber\n" " Reusch\n" " Schandhof\n" " Schnepfendorf ob der Tauber\n" " Steinbach\n" " Vorbach ob der Tauber\n\n" "91583: Schillingsfürst\n" " Altengreuth\n" " Bersbronn\n" " Faulenberg\n" " Leipoldsberg\n" " Neureuth\n" " Neuweiler\n" " Schillingsfürst\n" " Schorndorf\n" " Stilzendorf\n" " Wittum\n" " Wohnbach\n" " Ziegelhütte\n\n" "91583: Diebach\n" " Bellershausen\n" " Diebach\n" " Oberoestheim\n" " Unteroestheim\n" " Wolfsau\n\n" "91587: Adelshofen\n" "Adelshofen\n" " Gickelhausen\n" " Großharbach\n" " Haardt\n" " Neustett\n" " Ruckertshofen\n" " Tauberscheckenbach\n" " Tauberzell\n\n" "91592:\n" " Berbersbach am Wald\n" " Gastenfelden\n" " Hagenau am Wald\n" " Morlitzwinden am Wald\n" " Schönbronn\n" " Schweikartswinden\n" " Sengelhof\n" " Traisdorf\n\n" "91593: Burgbernheim\n" "Buchheim\n" " Burgbernheim\n" " Hilpertshof\n" " Hochbach\n" " Pfaffenhofen\n" " Schwebheim\n\n" "91598: Colmberg\n" "Auerbach\n" " Bieg am Wald\n" " Binzwangen\n" " Colmberg\n" " Häslabronn\n" " Kurzendorf\n" " Meuchlein\n" " Oberfelden\n" " Oberhegenau\n" " Poppenbach\n" " Unterfelden\n" " Unterhegenau\n\n" "91601: Dombühl\n" " Baimhofen\n" " Binsenweiler\n" " Bortenberg\n" " Dombühl\n" " Höfen\n" " Kloster Sulz\n" " Ziegelhaus\n\n" "91605: Gallmersgarten\n" "Bergtshofen 91605\n" " Gallmersgarten 91605\n" " Mörlbach 91605\n" " Steinach an der Ens 91605\n" " Steinach bei Rothenburg ob der Tauber 91605\n\n" "91607: Gebsattel\n" "Bockenfeld\n" " Eckartshof\n" " Gebsattel\n" " Kirnberg\n" " Pleikartshof\n" " Rödersdorf\n" " Speierhof\n" " Wildenhof\n\n" "91608: Geslau\n" " Aidenau\n" " Dornhausen\n" " Geslau\n" " Gunzendorf\n" " Hürbel\n" " Kreuth\n" " Lauterbach\n" " Oberbreitenau\n" " Oberndorf\n" " Reinswinden\n" " Schwabsroth\n" " Steinach am Wald\n" " Stettberg\n" " Unterbreitenau\n\n" "91610: Insingen\n" " Insingen 91610\n" " Leidenberg 91610\n" " Leuzhof 91610\n" " Lohr 91610\n" " Lohrbach 91610\n\n" "91613: Marktbergel\n" "Ermetzhof 91613\n" " Marktbergel 91613\n" " Ottenhofen 91613\n\n" "91616: Neusitz\n" "Erlbach ob der Tauber\n" " Horabach ob der Tauber\n" " Neusitz\n" " Schweinsdorf ob der Tauber\n" " Södelbronn ob der Tauber\n" " Wachsenberg ob der Tauber\n\n" "91620: Ohrenbach\n" " Gailshofen\n" " Gumpelshofen\n" " Habelsee\n" " Oberscheckenbach\n" " Ohrenbach\n" " Reichardsroth\n\n" "91628: Steinsfeld\n" " Bettwar\n" " Chausseehaus\n" " Ellwingshofen\n" " Endsee\n" " Gattenhofen\n" " Hartershofen\n" " Reichelshofen\n" " Steinsfeld\n" " Urphershofen\n\n" "91631: Wettringen\n" "Grüb\n" " Obergailnau\n" " Reichenbach\n" " Seemühle\n" " Taubermühle\n" " Untergailnau\n" " Wettringen\n\n" "91635: Windelsbach\n" "Birkach\n" " Burghausen\n" " Cadolzhofen\n" " Hornau\n" " Linden bei Rothenburg ob der Tauber\n" " Nordenberg bei Rothenburg ob der Tauber\n" " Preuntsfelden\n" " Windelsbach\n\n" "91637: Wörnitz\n" "Arzbach\n" " Bastenau\n" " Bottenweiler\n" " Erzberg\n" " Harlang\n" " Mittelstetten\n" " Oberwörnitz\n" " Walkersdorf\n" " Wörnitz\n\n" "97215: Uffenheim\n" "Brackenlohr\n" " Custenlohr\n" " Kleinharbach\n" " Langensteinach\n" " Rudolzhofen\n" " Uffenheim\n" " Uttenhofen\n" " Wallmersbach\n" " Welbhausen\n\n" "97215: Weigenheim\n" "Geckenheim 97215\n" " Reusch bei Würzburg 97215\n" " Weigenheim 97215\n\n" "97215: Simmershofen\n" " Adelhofen\n" " Auernhofen\n" " Equarhofen\n" " Hohlach\n" " Simmershofen\n" " Walkershofen\n\n" "97993: Creglingen\n" " Archshofen\n" " Blumweiler\n" " Craintal\n" " Creglingen\n" " Erdbach\n" " Finsterlohr\n" " Frauental\n" " Freudenbach\n" " Lichtel\n" " Lohrhof\n" " Münster\n" " Niederrimbach\n" " Niedersteinach\n" " Oberrimbach\n" " Reinsbronn\n" " Reutsachsen\n" " Schirmbach\n" " Schmerbach\n" " Schön\n" " Schonach\n" " Schwarzenbronn\n" " Sechselbach\n" " Seldeneck\n" " Waldmannshofen\n" " Weidenhof\n" " Weiler\n" " Wolfsbuch\n\n" "97996: Niederstetten\n" "Adolzhausen\n" " Dunzendorf\n" " Ebertsbronn\n" " Eichhof\n" " Ermershausen\n" " Hachtel\n" " Heimberg\n" " Herrenzimmern\n" " Niederstetten\n" " Oberstetten\n" " Pfitzingen\n" " Rinderfeld\n" " Rüsselhausen\n" " Sichertshausen\n" " Streichental\n" " Vorbachzimmern\n" " Wermutshausen\n" " Wildentierbach\n" " Wolkersfelden\n") subst = "\\t\\1" # 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