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

/
/
igm

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\\.]+%) identity"; final String string = "# /data/spine/bin/external/fasta/bin/glsearch36 -b 2 -m 9i -q /tmp/temp.seq /data/spine/databases/UniProt/sprot.compact_headers.distinct.mouse\n" + "GLSEARCH performs a global-query/local-library search\n" + " version 36.3.6 Nov, 2013(preload9)\n" + "Query: /tmp/temp.seq\n" + " 1>>>seq - 299 aa\n" + "Library: /data/spine/databases/UniProt/sprot.compact_headers.distinct.mouse\n" + " 9277236 residues in 16315 sequences\n\n" + "Statistics: Unscaled normal statistics: mu= -50.7059 var=2892.0306 Ztrim: 0\n" + " statistics sampled from 13365 (13367) to 13365 sequences\n" + "Algorithm: Global/Local affine Needleman-Wunsch (2007) (6.0 April 2007)\n" + "Parameters: BL50 matrix (15:-5), open/ext: -12/-2\n" + " Scan time: 11.560\n\n" + "The best scores are: n-w bits E(16315) %_id %_sim alen\n" + "SP|P61375|LHX5_MOUSE ( 402) 1361 66.3 5.7e-148 0.685 0.868 302\n" + "SP|P50481|LHX3_MOUSE ( 400) 331 30.8 1e-08 0.319 0.524 307\n\n" + ">>>seq, 299 aa vs /data/spine/databases/UniProt/sprot.compact_headers.distinct.mouse library\n\n" + ">>SP|P61375|LHX5_MOUSE (402 aa)\n" + " n-w opt: 1361 Z-score: 312.5 bits: 66.3 E(16315): 5.7e-148\n" + "global/local score: 1361; 68.5% identity (86.8% similar) in 302 aa overlap (1-299:107-400)\n\n" + " 10 20 30\n" + "seq YIDENKFVCKEDYLSNSSVAKENSLHSATT\n" + " :::::::::.::::.::. ::.::.:...\n" + "SP|P61 VRKARSKVFHLNCFTCMVCNKQLSTGEELYVIDENKFVCKDDYLSSSSL-KEGSLNSVSS\n" + " 80 90 100 110 120 130 \n\n" + " 40 50 60 70 80 90\n" + "seq GSDPSLSPDSQDPSQDDAKDSESANVSDKEGGSNENDDQNLGAKRRGPRTTIKAKQLETL\n" + " .: ::::: ::: ::: :...... :::: ..:::..:: :.:::::::::::::::::\n" + "SP|P61 CTDRSLSPDLQDPLQDDPKETDNSTSSDKETANNENEEQNSGTKRRGPRTTIKAKQLETL\n" + " 140 150 160 170 180 190 \n\n" + " 100 110 120 130 140 150\n" + "seq KAAFAATPKPTRHIREQLAQETGLNMRVIQVWFQNRRSKERRMKQLSALGARRHAFFRSP\n" + " ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::\n" + "SP|P61 KAAFAATPKPTRHIREQLAQETGLNMRVIQVWFQNRRSKERRMKQLSALGARRHAFFRSP\n" + " 200 210 220 230 240 250 \n\n" + " 160 170 180 190 200 210\n" + "seq RRMRPLVDRLEPGELIPNGPFSFYGDYQSEYYGPGGNYDFFPQGPPSSQAQTPVDLPFVP\n" + " :::::: ::. .:.. . :...::::::.::.:::::::: .:::: :::.:.: :. \n" + "SP|P61 RRMRPLGGRLDESEMLGSTPYTYYGDYQSDYYAPGGNYDFFAHGPPS-QAQSPADSSFLA\n" + " 260 270 280 290 300 310 \n\n" + " 220 230 240 250 260 \n" + "seq SSGPSGTPLGGLDHPLPGHHPSSEAQRFTDILAHPPGDSPSPEPSLPGPLHSMSAEVF--\n" + " .:::..::::.:. :: : : ... ::::...:: :.:::::.::: :: : .::: \n" + "SP|P61 ASGPGSTPLGALEPPLAGPH-GADNPRFTDMISHP--DTPSPEPGLPGALHPMPGEVFSG\n" + " 320 330 340 350 360 370 \n\n" + " 270 280 290 \n" + "seq GPSPPFSSLSVNGGASYGNHLSHP-PEMNEAA \n" + " :::::: ..: ..:.. :::: ::.:::: \n" + "SP|P61 GPSPPFP---MSGTSGYSGPLSHPNPELNEAAVW\n" + " 380 390 400 \n\n" + ">>SP|P50481|LHX3_MOUSE (400 aa)\n" + " n-w opt: 331 Z-score: 121.0 bits: 30.8 E(16315): 1e-08\n" + "global/local score: 331; 31.9% identity (52.4% similar) in 307 aa overlap (1-299:99-365)\n\n" + " 10 20 \n" + "seq YIDENKFVCK-EDYLSN-SSVAKENSLHSA\n" + " : .. : . .:.. . : .. \n" + "SP|P50 AERCFSRGESVYCKDDFFKRFGTKCAACQLGIPPTQVVRRAQDFVYHLHCFACVVCKRQL\n" + " 70 80 90 100 110 120 \n\n" + " 30 40 50 60 70 80 \n" + "seq TTGSDPSLSPDSQDPSQDDAKDSESANVSDKEGGSNENDDQNLGAKRRGPRTTIKAKQLE\n" + " .::.. : ::. . : :.:. . :. ::: ::::: :::::\n" + "SP|P50 ATGDEFYLMEDSRLVCK---ADYETAKQREAEAT----------AKR--PRTTITAKQLE\n" + " 130 140 150 160 170 \n\n" + " 90 100 110 120 130 140 \n" + "seq TLKAAFAATPKPTRHIREQLAQETGLNMRVIQVWFQNRRSKERRMKQLSALGARRHAFFR\n" + " :::.:. ..:::.::.::::..::::.:::.::::::::.::.:.:. .: : .::\n" + "SP|P50 TLKSAYNTSPKPARHVREQLSSETGLDMRVVQVWFQNRRAKEKRLKK-DAGRQRWGQYFR\n" + " 180 190 200 210 220 230 \n\n" + " 150 160 170 180 190 200 \n" + "seq SPRRMRPLVDRLEPGELIPNGPFSFYGDYQSEYYGPGGNYDFFPQGPPSSQAQTPVDLPF\n" + " . .: : : .: .: : .. . :: . :.. .\n" + "SP|P50 NMKRSRG----------------SSKSDKDSIQEGQDSDAEVSFTDEPSMADMGPANGLY\n" + " 240 250 260 270 \n\n" + " 210 220 230 240 250 260 \n" + "seq VPSSGPS---GTPLGGLDHPLPGHHPSSEAQRFTDILAHPP-GDSPSPEP--SLPGPLHS\n" + " . :. : :.::: : . ... .. : : ::: ::::: \n" + "SP|P50 SSLGEPAPALGRPVGGLGSFTLDHGGLTGPEQYRELRPGSPYGIPPSPAAPQSLPGPQPL\n" + " 280 290 300 310 320 330 \n\n" + " 270 280 290 \n" + "seq MSAEVFGPSPPFSSLSVNGGASYGNHLSHPPEMNEAA \n" + " .:. :. : ..::. .. :. :: : : \n" + "SP|P50 LSSLVY----PDTNLSLVPSGPPGG----PPPMRVLAGNGPSSDLSTESSSGYPDFPASP\n" + " 340 350 360 370 380 \n\n" + "SP|P50 ASWLDEVDHAQF\n" + " 390 400\n\n\n" + ">>>///\n\n" + "299 residues in 1 query sequences\n" + "9277236 residues in 16315 library sequences\n" + " Tcomplib [36.3.6 Nov, 2013(preload9)] (8 proc in memory [0G])\n" + " start: Thu Sep 3 20:44:48 2015 done: Thu Sep 3 20:44:55 2015\n" + " Total Scan time: 11.560 Total Display time: 0.010\n\n" + "Function used was GLSEARCH [36.3.6 Nov, 2013(preload9)]"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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