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 = "(\\d{10})_([A-Z][a-z]+)([A-Z][a-z]+)(\\.[a-zA-Z]{3,4})"; final String string = "1173216167_AgentWill.jpg\n" + "1173216768_BrooksHarold.jpg\n" + "1173299189_BurgessDon.jpg\n" + "1173299407_ConiglioMike.jpg\n" + "1173299438_CooperKaren.jpg\n" + "1173299499_CurtisChristopher.jpg\n" + "1173300038_ElmoreKim.jpg\n" + "1173300155_FarmerVicki.jpg\n" + "1173300181_FletcherSteve.jpg\n" + "1173300207_ForrenEddie.jpg\n" + "1173300279_McguckinLinda.jpg\n" + "1173300440_GourleyJj.jpg\n" + "1173300567_HeinslemanPam.jpg\n" + "1173300593_HondlKurt.jpg\n" + "1173300619_HornJeff.jpg\n" + "1173300646_HowardKen.jpg\n" + "1173300716_IvicIgor.jpg\n" + "1173300757_JainMike.jpg\n" + "1173300862_KainJack.jpg\n" + "1173302066_KennedyDoug.jpg\n" + "1173302338_KuhlmanKristin.jpg\n" + "1173302528_LangstronCarrie.jpg\n" + "1173302580_LynnKelly.jpg\n" + "1173302631_MacgormanDon.jpg\n" + "1173303489_MelnikovValery.jpg\n" + "1173303530_MorrowBrett.jpg\n" + "1173303596_MurnanJames.jpg\n" + "1173303818_OrtegaKiel.jpg\n" + "1173304172_RabinBob.jpg\n" + "1173304254_RollinsTonia.jpg\n" + "1173304421_SchmidtMike.jpg\n" + "1173304508_SchurrTerry.jpg\n" + "1173304851_StumpfGreg.jpg\n" + "1173304935_TarpKeli.jpg\n" + "1173305069_ToomeyRobert.jpg\n" + "1173305102_TorresSebastian.jpg\n" + "1173305301_WickerLou.jpg\n" + "1173305326_WittArthur.jpg\n" + "1173305357_WoodBim.jpg\n" + "1173305420_XuQin.jpg\n" + "1173305550_YussoufNusrat.jpg\n" + "1173305582_ZahraiAllen.jpg\n" + "1173305608_ZhangPengfei.jpg\n" + "1173305634_ZhangJian.jpg\n" + "1173305666_ZieglerConrad.jpg\n" + "1173305696_ZrnicDusan.jpg\n" + "1178031443_LewisJohn.jpg\n" + "1208811784_DoviakRichard.jpg\n" + "1208811993_KrauseJohn.jpg\n" + "1208812047_MansellTed.jpg\n" + "1208812483_PepplerRandy.jpg\n" + "1208812511_ReevesHeather.jpg\n" + "1208812542_RobertsBrett.jpg\n" + "1208812597_WaughSean.jpg\n" + "1248986831_Warde-David.jpg\n" + "1248987295_Smith--Travis.jpg\n" + "1248987685_Knopfmeier--Kent.jpg\n" + "1248987721_GRIFFIN-ERICA.jpg\n" + "1248987828_Brogden--Jeff.jpg\n" + "1248987872_Arthur-Ami.jpg\n" + "1249399247_Nemunaitis-Kodi.jpg\n" + "1258400095_Clark-Adam.jpg\n" + "1258400182_Stratman-Derek.jpg\n" + "1258755192_Schwarz--Chris.jpg\n" + "1271793238_humberto.jpg\n" + "1273024015_BrianKaney2003.jpg\n" + "1278003921_Butler-Sterling.jpg\n" + "1278004017_Reinke-Tracy.jpg\n" + "1278004036_Ryzhkov-Alexander.jpg\n" + "1278004055_Tang-Lin.jpg\n" + "1278004074_Wang-Yadong.jpg\n" + "1297362249_Jones-Thomas.jpg\n" + "1297362283_Potvin-Corey.jpg\n" + "1311024411_Crank-Linda.jpg\n" + "1311024437_Gao-Jidong.jpg\n" + "1311024633_Smith-Brandon.jpg\n" + "1391808396_Bowden-Katie.jpg\n" + "1401375264_Meitin_jose.jpg\n" + "1407171270_Carlin_Jacob.jpg\n" + "1407171306_Cocks_Stephen.jpg\n" + "1407171371_Creager_Gerald.jpg\n" + "1407171682_Kirstetter-Pierre.jpg\n" + "1407171749_Kuster_Charles.jpg\n" + "1407171773_Martinaitis_Steven.jpg\n" + "1407171792_Mirkovic_Djordje.jpg\n" + "1407171905_Shattuck_Micheal.jpg\n" + "1407171947_Snyder_Jeffrey.jpg\n" + "1407172034_Wadler_Joshua.jpg\n" + "1418052845_D-Wasielewski.jpg"; 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