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"^(.*)(\r?\n\1)+$", flags=re.MULTILINE) test_str = ("{\"??\", \"What?\"}\n" "{\"0mg\", \"Oh My God\"},\n" "{\"0wn\", \"owned\"},\n" "{\"10\\\\/3u\", \"love you\"},\n" "{\"13wt\", \"Loot\"},\n" "{\"2\", \"too\"},\n" "{\"31337\", \"elite\"},\n" "{\"4tw\", \"for the win\"},\n" "{\"A&D\", \"Attack and Defend\"},\n" "{\"AFAIK\", \"As Far As I Know\"},\n" "{\"AFK\", \"Away from keyboard\"},\n" "{\"ASL\", \"Age Sex Location\"},\n" "{\"ATM\", \"At The Moment\"},\n" "{\"BAF\", \"Bring A Friend\"},\n" "{\"BBIM\", \"Be Back In a Minute\"},\n" "{\"BBL\", \"Be Back Later\"},\n" "{\"BBS\", \"Be Back Soon\"},\n" "{\"BFG\", \"big fucking gun\"},\n" "{\"BRB\", \"Be Right Back\"},\n" "{\"BS\", \"Bullshit\"},\n" "{\"BTW\", \"By The Way\"},\n" "{\"Camper\", \"Ambush\"},\n" "{\"CFT\", \"Capture the flag\"},\n" "{\"CTF\", \"Capture the Flag\"},\n" "{\"CU\", \"See You\"},\n" "{\"d00d\", \"Dude\"},\n" "{\"DM\", \"Death Match\"},\n" "{\"DMG\", \"Damage\"},\n" "{\"dog8\", \"dog\"},\n" "{\"duma**\", \"idiot\"},\n" "{\"eet\", \"elite\"},\n" "{\"em\", \"Them\"},\n" "{\"exp\", \"experience points\"},\n" "{\"EXP\", \"Experience Points\"},\n" "{\"f00\", \"Fool\"},\n" "{\"FAQ\", \"Frequently Asked Questions\"},\n" "{\"FB\", \"Flash Bang grenade\"},\n" "{\"FFA\", \"Free For All\"},\n" "{\"FFS\", \"For Fuck's Sake\"},\n" "{\"FH\", \"Full Health\"},\n" "{\"Flak\", \"Debris\"},\n" "{\"Flame\", \"Nonstop insulting\"},\n" "{\"form\", \"from\"},\n" "{\"FPS\", \"First Person Shooter\"},\n" "{\"fragged\", \"killed\"},\n" "{\"ftw\", \"for the win\"},\n" "{\"G2G\", \"Got To Go\"},\n" "{\"GA\", \"Go Ahead\"},\n" "{\"GD\", \"God Damn\"},\n" "{\"GF\", \"Good Fight\"},\n" "{\"GG\", \"Good Game\"},\n" "{\"GGA\", \"Good Game All\"},\n" "{\"gimme\", \"Give me\"},\n" "{\"GL\", \"Good Luck\"},\n" "{\"Going Gold\", \"publishing of software\"},\n" "{\"grill\", \"girl\"},\n" "{\"guise\", \"guys\"},\n" "{\"h@\", \"Hat\"},\n" "{\"h4x\", \"hacks\"},\n" "{\"h4x0r\", \"hacker\"},\n" "{\"h8\", \"Hate\"},\n" "{\"hai\", \"hi\"},\n" "{\"high-ping bastard\", \"crappy internet\"},\n" "{\"HP\", \"Health Points\"},\n" "{\"IIRC\", \"If I Recall Correctly\"},\n" "{\"IMHO\", \"In My Honest Opinion\"},\n" "{\"IMO\", \"In My Opinion\"},\n" "{\"instagib\", \"unlimited ammo\"},\n" "{\"IRC\", \"Internet Relay Chat\"},\n" "{\"IRL\", \"In Real Life\"},\n" "{\"j0\", \"Yo!\"},\n" "{\"J00\", \"You!\"},\n" "{\"JJ\", \"Just Joking\"},\n" "{\"JK\", \"Just Kidding\"},\n" "{\"kewl\", \"cool\"},\n" "{\"kicked\", \"banned cheater\"},\n" "{\"kk\", \"ok\"},\n" "{\"KOS\", \"Kill On Sight\"},\n" "{\"l@ym\", \"laughing at your momma\"},\n" "{\"l337\", \"elite\"},\n" "{\"l33t\", \"Elite\"},\n" "{\"l4m3r\", \"lamer\"},\n" "{\"level up\", \"Improving\"},\n" "{\"liek\", \"like\"},\n" "{\"lobby\", \"chat room\"},\n" "{\"LOL\", \"Laughs out loud\"},\n" "{\"lopl\", \"lol\"},\n" "{\"low-ping bastard\", \"fast internet\"},\n" "{\"Lvl\", \"Level\"},\n" "{\"m2\", \"me too\"},\n" "{\"m8\", \"mate\"},\n" "{\"Mana\", \"cast magical spells\"},\n" "{\"mastah\", \"master\"},\n" "{\"max0r\", \"max\"},\n" "{\"Med\", \"Medic\"},\n" "{\"meh\", \"oh well\"},\n" "{\"MMORPG\", \"Massive Multiplayer Online Role Playing Game\"},\n" "{\"Mod\", \"A modification of a game\"},\n" "{\"MP\", \"Multiplayer\"},\n" "{\"MTFBWY\", \"May The Force Be With You\"},\n" "{\"n00b\", \"newbie\"},\n" "{\"N1\", \"Nice one\"},\n" "{\"Nade\", \"Grenade\"},\n" "{\"nd\", \"and\"},\n" "{\"Nerfed\", \"bad bug\"},\n" "{\"newb\", \"newcomer\"},\n" "{\"nooblet\", \"newcomer\"},\n" "{\"np\", \"No problem\"},\n" "{\"NT\", \"nice try\"},\n" "{\"OLO\", \"LOL\"},\n" "{\"OMDG\", \"oh my dance\"},\n" "{\"OMFG\", \"Oh My Fucking God\"},\n" "{\"OMG\", \"oh my god\"},\n" "{\"OMGWTFBBQ\", \"Oh My God What The Fuck Barbecue\"},\n" "{\"OMW\", \"On My Way\"},\n" "{\"OOR\", \"Out Of Range\"},\n" "{\"OOS\", \"Out Of Sight\"},\n" "{\"ORLY\", \"Oh, really?\"},\n" "{\"ORLY\", \"Oh, really?\"},\n" "{\"OSOK\", \"One Shot One Kill\"},\n" "{\"own\", \"own\"},\n" "{\"ownage\", \"superior\"},\n" "{\"p0wn\", \"pawned\"},\n" "{\"ph33r\", \"Fear me\"},\n" "{\"phear\", \"fear\"},\n" "{\"PITA\", \"Pain In The Arse/Ass\"},\n" "{\"PK\", \"Player Killing\"},\n" "{\"pl0x\", \"please\"},\n" "{\"PMGZ\", \"OMG\"},\n" "{\"PMSL\", \"Pissing MySelf Laughing\"},\n" "{\"Polishing\", \"final touches\"},\n" "{\"Port\", \"Teleport\"},\n" "{\"powwah\", \"power\"},\n" "{\"Pr0n\", \"porn\"},\n" "{\"pwnage\", \"superior\"},\n" "{\"pwnt\", \"superior\"},\n" "{\"r\", \"are\"},\n" "{\"r0x0r\", \"dude that rocks!\"},\n" "{\"rgr\", \"Roger\"},\n" "{\"ROFL\", \"Rolls on the floor laughing\"},\n" "{\"ROFLMAO\", \"Rolling On the Floor Laughing My Ass Off\"},\n" "{\"rox\", \"Rocks\"},\n" "{\"RP\", \"Role Play\"},\n" "{\"RPG\", \"Role-Playing Game\"},\n" "{\"RT\", \"Roger That\"},\n" "{\"RTFM\", \"Read the f***ing manual\"},\n" "{\"RTS\", \"Real-Time Strategy\"},\n" "{\"Sig\", \"Signature\"},\n" "{\"sk1llz\", \"Skills\"},\n" "{\"Slug\", \"A large, non-self-propelled projectile\"},\n" "{\"smat\", \"smart\"},\n" "{\"SP\", \"Single Player\"},\n" "{\"Spam\", \"Repeatedly messaging the same messages\"},\n" "{\"spawn\", \"reborn\"},\n" "{\"sry\", \"Sorry\"},\n" "{\"STFU\", \"Shut The Fuck UP\"},\n" "{\"sup\", \"What's Up\"},\n" "{\"sux0r\", \"Sucks\"},\n" "{\"taunt\", \"Provoking\"},\n" "{\"TBH\", \"To Be Honest\"},\n" "{\"teh\", \"the\"},\n" "{\"Thx\", \"Thanks\"},\n" "{\"TPS\", \"Third Person Shooter\"},\n" "{\"Ty\", \"Thank you\"},\n" "{\"u\", \"you\"},\n" "{\"w8\", \"wait\"},\n" "{\"wat\", \"what\"},\n" "{\"WB\", \"Welcome Back\"},\n" "{\"wen\", \"when\"},\n" "{\"whut\", \"what\"},\n" "{\"winnar\", \"winner\"},\n" "{\"wot\", \"what\"},\n" "{\"WTF\", \"What the f***?\"},\n" "{\"WTG\", \"Way To Go\"},\n" "{\"WYG\", \"What You Got?\"},\n" "{\"y\", \"why\"},\n" "{\"ya\", \"yeah\"},\n" "{\"yass\", \"yes\"},\n" "{\"yea\", \"yeah\"},\n" "{\"yos\", \"yes\"},\n" "{\"yus\", \"yes\"},\n" "{\"ZPMG\", \"OMG\"},") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} 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