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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^(.*)(\\r?\\n\\1)+$"; final String string = "{\"??\", \"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\"},"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html