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

/
/
gJi

Test String

Code Generator

Language

Generated Code

$re = '/(?:Term\sFreq\sVector:\s<br>(?:(([a-zA-Z0-9_\.]+)):([0-9]+),\s(?:[0-9\.]+)\s?)+(:?.*))+/Ji'; $str = '<ul><li><div class="ResultURLStyle"><a href="DocumentViewer?id=147522" target="_blank">FR941206-0-00005</a></div><div class="ResultURLStyle">Term Freq Vector: <br>bone:39, 169.98874 meat:24, 126.80792 separ:13, 17.930304 remov:12, 20.017244 tissu:10, 449.1114 fsi:9, 2708.487 mechan:9, 30.070314 muscl:9, 196.8524 debon:8, 8658.278 hand:7, 9.698391 ms:7, 60.36747 high:5, 5.665258 knive:5, 1002.19165 machineri:5, 108.53987 product:5, 6.3933544 result:5, 5.424931 health:4, 16.835772 includ:4, 3.6064584 livestock:4, 264.0775 manufactur:4, 14.436775 safeti:4, 26.27114 advanc:3, 16.430393 aspect:3, 35.604355 conform:3, 88.36456 crush:3, 159.37085 determin:3, 9.746535 differ:3, 18.565628 emerg:3, 14.869228 finish:3, 26.112677 machin:3, 41.111153 natur:3, 13.428124 oper:3, 4.980621 physic:3, 43.387413 process:3, 9.041892 pulver:3, 3971.0903 recoveri:3, 24.429 regul:3, 11.099191 report:3, 3.6940117 skelet:3, 2445.162 speed:3, 36.789845 surfac:3, 50.190536 system:3, 6.8322706 action:2, 7.82278 cfr:2, 23.517454 consist:2, 19.387527 deriv:2, 68.228264 descript:2, 65.22043 e.g:2, 113.28936 equip:2, 17.05211 essenti:2, 32.713223 expect:2, 5.1537876 grind:2, 448.72983 held:2, 8.619702 inspect:2, 28.522709 intact:2, 240.72699 intend:2, 16.388079 knife:2, 354.94287 marrow:2, 1814.9656 materi:2, 16.067507 miner:2, 88.914986 obtain:2, 19.321566 occur:2, 23.650143 particl:2, 528.155 past:2, 8.308373 press:2, 12.855492 pressur:2, 13.348708 recogn:2, 40.658585 scrape:2, 615.56525 shave:2, 516.2805 siev:2, 3181.6567 techniqu:2, 69.439255 tradit:2, 19.159653 wizard:2, 1281.9296 address:1, 14.368437 agenc:1, 9.194739 amount:1, 11.925466 appli:1, 14.673825 applic:1, 13.707986 attach:1, 52.235683 background:1, 41.210598 believ:1, 11.743041 boneless:1, 4126.211 broken:1, 63.51834 classifi:1, 130.11949 clerk:1, 191.49927 close:1, 6.44453 comminut:1, 11237.341 commonli:1, 226.57872 connect:1, 22.29631 consequ:1, 42.92896 constitu:1, 81.44256 consum:1, 18.714964 content:1, 38.61347 contrast:1, 42.265926 copi:1, 26.827602 counter:1, 49.46661 cover:1, 13.109487 data:1, 20.2957 decad:1, 24.477684 detail:1, 16.240429 develop:1, 4.924017 devic:1, 61.527843 difficulti:1, 26.50316 docket:1, 59.840813 effect:1, 6.4812245 effici:1, 29.289873 emploi:1, 15.682959 emul:1, 500.1468 entitl:1, 51.23739 establish:1, 8.490146 exerci:1, 34.371666 fed:1, 103.094864 final:1, 7.307171 forc:1, 6.1383395 fr:1, 19.05596 fragment:1, 177.5311 fundament:1, 41.453182 good:1, 6.0453844 ground:1, 17.304644 hard:1, 14.797988 ii:1, 25.01326 incorpor:1, 49.666634 involv:1, 8.61141 led:1, 12.976781 linkag:1, 504.92828 loin:1, 3827.2102 longstand:1, 469.8888 made:1, 3.9924936 maintain:1, 12.610849 manner:1, 37.199253 minut:1, 20.582813 modern:1, 32.888412 monitor:1, 33.31788 normal:1, 30.871815 occurr:1, 348.61716 offic:1, 5.2373466 open:1, 6.2924285 panel:1, 62.253063 passag:1, 29.371315 percept:1, 124.85934 piec:1, 38.94087 possibl:1, 16.787077 potenti:1, 14.408812 practic:1, 12.41987 pre:1, 18.724916 preci:1, 45.311855 procedur:1, 18.64559 public:1, 4.9878173 qualiti:1, 18.36997 recommend:1, 20.264551 render:1, 114.96626 resist:1, 36.608788 rib:1, 532.95154 safe:1, 43.083042 screen:1, 59.530544 select:1, 21.929705 shape:1, 45.339085 sight:1, 80.49916 similar:1, 15.7118845 small:1, 9.254025 soft:1, 88.9749 stride:1, 322.43896 structur:1, 17.082443 supermarket:1, 152.42569 support:1, 5.8038373 term:1, 6.77817 touch:1, 39.420437 tremend:1, 113.143745 type:1, 6.134703 unavoid:1, 386.92673 volum:1, 23.309868 wholesom:1, 1496.189</div><div class="ResultSnippetStyle">past decad fsi monitor tremend stride modern meat <B>bone</B> separ machineri fsi determin meat <B>bone</B> separ skelet muscl tissu <B>bone</B> remov muscl tissu livestock <B>bone</B> machin classifi meat <B>bone</B> separ develop emul physic action hand held high speed knive remov skelet muscl tissu <B>bone</B> e.g wizard knife advanc meat <B>bone</B> separ led recoveri system separ meat <B>bone</B> crush grind pulver <B>bone</B> meat remov shave press scrape muscl tissu <B>bone</B> surfac similar action hand held high speed knive meat obtain manner obtain tradit</div></li><li><div class="ResultURLStyle"><a href="DocumentViewer?id=142466" target="_blank">FR940303-1-00058</a></div><div class="ResultURLStyle">Term Freq Vector: <br>bone:36, 169.98874 meat:23, 126.80792 mechan:12, 30.070314 tissu:11, 449.1114 debon:10, 8658.278 separ:9, 17.930304 ms:8, 60.36747 muscl:8, 196.8524 advanc:7, 16.430393 machineri:7, 108.53987 process:7, 9.041892 materi:6, 16.067507 recoveri:6, 24.429 regul:6, 11.099191 remov:6, 20.017244 skelet:6, 2445.162 adher:5, 111.75518 fsi:5, 2708.487 livestock:5, 264.0775 result:5, 5.424931 system:5, 6.8322706 carcass:4, 1509.0143 crush:4, 159.37085 hand:4, 9.698391 health:4, 16.835772 product:4, 6.3933544 pulver:4, 3971.0903 report:4, 3.6940117 safeti:4, 26.27114 soft:4, 88.9749 tradit:4, 19.159653 appli:3, 14.673825 aspect:3, 35.604355 deriv:3, 68.228264 equip:3, 17.05211 grind:3, 448.72983 hard:3, 14.797988 high:3, 5.665258 includ:3, 3.6064584 oper:3, 4.980621 pressur:3, 13.348708 size:3, 20.973513 type:3, 6.134703 amount:2, 11.925466 applic:2, 13.707986 attach:2, 52.235683 believ:2, 11.743041 broken:2, 63.51834 cfr:2, 23.517454 consist:2, 19.387527 differ:2, 18.565628 emerg:2, 14.869228 final:2, 7.307171 finish:2, 26.112677 fr:2, 19.05596 gener:2, 4.0578303 inspect:2, 28.522709 intact:2, 240.72699 intend:2, 16.388079 knive:2, 1002.19165 machin:2, 41.111153 manufactur:2, 14.436775 marrow:2, 1814.9656 part:2, 4.197703 particl:2, 528.155 raw:2, 78.95874 siev:2, 3181.6567 small:2, 9.254025 start:2, 6.998397 techniqu:2, 69.439255 accur:1, 81.00537 address:1, 14.368437 agenc:1, 9.194739 anatom:1, 4632.9385 apertur:1, 3162.6047 background:1, 41.210598 button:1, 304.23676 capabl:1, 33.452938 characterist:1, 67.45274 classif:1, 232.36032 clerk:1, 191.49927 compar:1, 11.829044 compat:1, 171.4789 composit:1, 60.471146 conform:1, 88.36456 consequ:1, 42.92896 content:1, 38.61347 contrast:1, 42.265926 convent:1, 42.03048 copi:1, 26.827602 cover:1, 13.109487 current:1, 9.162041 data:1, 20.2957 depend:1, 18.96904 detail:1, 16.240429 determin:1, 9.746535 devic:1, 61.527843 due:1, 11.871586 e.g:1, 113.28936 effect:1, 6.4812245 effici:1, 29.289873 emploi:1, 15.682959 entitl:1, 51.23739 essenti:1, 32.713223 fact:1, 10.2055 feather:1, 544.4897 fed:1, 103.094864 feder:1, 7.2581663 forc:1, 6.1383395 fragment:1, 177.5311 handl:1, 25.016815 hear:1, 20.273108 ii:1, 25.01326 incorpor:1, 49.666634 interconnect:1, 575.3322 involv:1, 8.61141 label:1, 72.55873 limit:1, 10.105716 link:1, 17.927868 loin:1, 3827.2102 manner:1, 37.199253 medium:1, 45.703964 method:1, 25.768686 miner:1, 88.914986 natur:1, 13.428124 occur:1, 23.650143 offic:1, 5.2373466 open:1, 6.2924285 origin:1, 16.382486 panel:1, 62.253063 pass:1, 15.116921 passag:1, 29.371315 past:1, 8.308373 physic:1, 43.387413 piec:1, 38.94087 potenti:1, 14.408812 powder:1, 273.23074 pre:1, 18.724916 press:1, 12.855492 public:1, 4.9878173 push:1, 24.280756 qualiti:1, 18.36997 recommend:1, 20.264551 reflect:1, 15.122981 relev:1, 43.739544 resist:1, 36.608788 rib:1, 532.95154 scrape:1, 615.56525 screen:1, 59.530544 select:1, 21.929705 shave:1, 516.2805 smaller:1, 33.1714 suffici:1, 30.671022 support:1, 5.8038373 surfac:1, 50.190536 technolog:1, 17.411894 term:1, 6.77817 typic:1, 48.848965 understand:1, 17.468332 vari:1, 63.16888 volum:1, 23.309868 warrant:1, 71.410</div><div class="ResultSnippetStyle">contrast mechan tradit mechan debon machin ms result involv mechan separ remov <B>bone</B> attach skelet muscl livestock applic high pressur crush grind pulver <B>bone</B> meat remov high pressur forc result past siev separ <B>bone</B> particl fragment result crush pulver <B>bone</B> process due mechan machineri manufactur ms <B>bone</B> <B>bone</B> particl includ <B>bone</B> marrow incorpor finish product regul ms 9 cfr 319.5 type equip separ remov <B>bone</B> intend cover product manufactur machineri oper differ resist hard <B>bone</B> soft tissu passag</div></li></ul> '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php