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

r"
"
gs

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('([0-9]{12}) AAXX \\d{5} ([/|\\d]{5}) [/|\\d]{5} ([/|\\d]{1})([/|\\d]{2})([/|\\d]{2})( (1[/\\d]*)|)( (2[/\\d]*)|)(\\s*(3[/\\d]*)|)(\\s*(4[/\\d]*)|)(\\s*(5[/\\d]*)|)(\\s*(6[/\\d]*)|)(\\s*(7[/\\d]*)|)(\\s*(8[/\\d]*)|)\\s*333\\s*', 'gs') const str = ` ########################################################## # Query made at 11/09/2018 18:33:45 UTC ########################################################## ########################################################## # latest SYNOP reports from United Kingdom before 11/09/2018 18:33:45 UTC ########################################################## 201811091800 AAXX 09184 03002 15461 /1430 10096 20070 30018 40036 56021 60002 333 10102 82/19 86/28 91041 90710 91141== 201811091800 AAXX 09184 03005 15460 /1431 10090 20061 39920 40019 56025 60002 333 10096 55300 20000 87/14 90710 91142== 201811091800 AAXX 09184 03008 17459 /1327 10097 20074 39923 49995 57027 60002 704// 333 10102 87/14 90710 91142 91041 555 7/097= 201811091800 AAXX 09184 03010 46/// /1344 10108 20074 49900 57035 333 90710 91154== 201811091800 AAXX 09184 03017 15461 /1329 10100 20072 39922 49953 58037 69902 333 10107 55300 20000 83/18 87/39 91039 90710 91141== 201811091800 AAXX 09184 03026 15771 /1233 10111 20066 39814 49832 58047 69982 333 10114 55300 20000 88/50 90710 91141== 201811091800 AAXX 09184 03031 15580 /1219 10085 20052 39556 49873 57042 69902 333 10087 55300 20000 88/22 90710 91129== 201811091800 AAXX 09184 03034 15684 /1220 10119 20052 39832 49845 57049 69902 333 10122 86/43 85/63 90710 91130== 201811091800 AAXX 09184 03039 46/// /1048 10057 20049 333 10058 91071 90710 91171== 201811091800 AAXX 09184 03044 15573 /1030 10098 20063 39794 49890 58039 60002 333 10105 55300 20000 82/23 91043 90710 91150== 201811091800 AAXX 09184 03047 17471 /1422 10085 20058 39572 49865 58049 60032 781// 333 10090 553// 20000 87/18 85/25 91040 90710 91140== 201811091600 AAXX 09164 03062 45575 /1424 10105 20065 39921 49926 58044 333 553// 20119 85/28 90710 91138== 201811091800 AAXX 09184 03063 15580 /1512 10103 20053 39629 49898 56041 69902 333 10106 55300 20000 86/25 86/31 90710 91125== 201811091800 AAXX 09184 03065 46/// /1491 10017 20017 333 10018 91099 00101 90710 91199 00108== 201811091800 AAXX 09184 03066 17581 /1322 10113 20067 39899 49905 56044 69902 723// 333 10115 55300 20000 85/24 86/31 91033 90710 91133== 201811091800 AAXX 09184 03068 12580 81323 10107 20069 39904 49913 58042 60002 885// 333 10113 84620 87630== 201811091800 AAXX 09184 03072 46/// /1458 10037 20037 333 10037 91079 90710 91179== 201811091800 AAXX 09184 03075 15459 /1230 10103 20073 39889 49932 56042 69902 333 10106 84/16 86/24 91044 90710 91144== 201811091800 AAXX 09184 03080 15463 /1319 10095 20076 39758 49925 56045 69902 333 10096 88/10 90710 91137== 201811091800 AAXX 09184 03088 17361 /1535 10096 20084 39770 49929 58049 60002 704// 333 10097 553// 20000 88/07 91048 90710 91148== 201811091800 AAXX 09184 03091 15461 /1519 10101 20079 39863 49940 57045 60002 333 10106 55300 20000 87/12 86/19 91037 90710 91137== 201811091800 AAXX 09184 03100 17537 /1338 10097 20083 39779 49795 56045 60082 761// 333 10114 55300 20000 81/21 86/37 91048 90710 91152== 201811091800 AAXX 09184 03105 17661 /1335 10098 20080 39779 49796 56056 60062 761// 333 10116 86/38 83/50 91048 90710 91148== 201811091800 AAXX 09184 03111 16450 /1334 10098 20085 39800 49812 56054 60192 333 10110 81/13 86/45 91045 90710 91148== 201811091800 AAXX 09184 03132 17642 /1230 10101 20089 39827 49840 56053 60082 762// 333 10113 85/38 85/46 91040 90710 91140== 201811091800 AAXX 09184 03134 17580 /1317 10100 20072 39797 49867 56045 60012 723// 333 10102 55300 20000 82/20 83/26 86/60 90710 91126== 201811091800 AAXX 09184 03136 17571 /1421 10113 20073 39824 49856 56045 69962 781// 333 10116 55300 20000 81/27 84/45 85/60 90710 91131== 201811091800 AAXX 09184 03144 15580 /1011 10103 20066 39858 49899 56044 69922 333 10113 553// 20000 88/20 91021 90710 91127== 201811091800 AAXX 09184 03148 46/// /1335 10053 20051 333 10058 91048 90710 91150== 201811091800 AAXX 09184 03153 17557 /1427 10097 20081 39732 49866 56046 69942 782// 333 10108 55300 20000 82/33 87/47 91038 90710 91141== 201811091500 AAXX 09154 03155 46482 /1521 10091 20061 39633 49923 58049 333 86/18 85/23 91031 90710 91137== 201811091800 AAXX 09184 03158 15470 /1316 10096 20074 39781 49914 56051 60002 333 10108 55300 20000 88/12== 201811091800 AAXX 09184 03162 17480 /1415 10089 20069 39621 49899 56047 69902 723// 333 10090 55300 20000 87/10 84/20 91025 90710 91125== 201811091800 AAXX 09184 03166 17466 /1114 10100 20074 39827 49895 58046 69902 757// 333 10115 55300 20000 87/18 90710 91130== 201811091800 AAXX 09184 03171 15460 /1420 10105 20084 39906 49918 56042 60002 333 10105 55300 20000 88/12 90710 91132== 201811091800 AAXX 09184 03204 11450 81331 10101 20086 39824 49843 56059 60072 76362 885// 333 10117 55300 20000 81713 88628 91041 90710 91141== 201811091800 AAXX 09184 03210 16541 /1433 10093 20075 39724 49871 56045 69982 333 10108 81/29 87/44 91048 90710 91148== 201811091800 AAXX 09184 03212 17562 /1313 10105 20073 39796 49892 57046 69902 781// 333 10120 83/20 84/24 86/31 91023 90710 91128== 201811091800 AAXX 09184 03214 17758 /1322 10100 20080 39870 49888 58044 69982 782// 333 10118 86/50 84/58 90710 91135== 201811091800 AAXX 09184 03220 16984 ///// 10112 20076 39865 49898 56047 60002 333 10112 87/61== 201811091800 AAXX 09184 03224 15268 /1422 10084 20072 39571 49907 56052 60002 333 10084 81/04 87/62 90710 91131== 201811091800 AAXX 09184 03225 16583 /1719 10096 20057 39607 49903 58048 60002 333 10097 55300 20000 81/21 84/38 85/60 90710 91134== 201811091800 AAXX 09184 03226 15584 /1621 10092 20063 39642 49910 57047 60002 333 10094 81/27 84/61 90710 91129== 201811091800 AAXX 09184 03227 46/// /1741 10043 20043 333 10050 91051 90710 91152== 201811091800 AAXX 09184 03230 16358 /1415 10087 20078 39670 49921 56050 60002 333 10088 88/07 90710 91127== 201811091800 AAXX 09184 03238 15467 /1610 10099 20081 39754 49922 56049 60002 333 10099 88/10 91021== 201811091800 AAXX 09184 03240 17359 /1322 10102 20089 39907 49934 56049 60002 704// 333 10103 55300 20000 81/09 86/14 85/50 90710 91132== 201811091800 AAXX 09184 03257 15471 /1514 10105 20086 39896 49935 57045 69902 333 10106 55300 20000 83/12 85/63 90710 91127== 201811091800 AAXX 09184 03265 17981 /1420 10104 20087 39911 49941 57042 69902 722// 333 10106 83/62 84/65 85/69 90710 91129== 201811091800 AAXX 09184 03266 16969 /1515 10108 20080 39927 49944 56041 69902 333 10109 84/63 91025 90710 91125== 201811091800 AAXX 09184 03275 17471 /1525 10098 20084 39758 49946 56042 69902 723// 333 10104 84/11 86/35 90710 91134== 201811091800 AAXX 09184 03281 16/// /1618 10087 20081 69922 333 10101 90710 91127== 201811091800 AAXX 09184 03292 169// /1625 10108 20092 39947 49965 56033 60002 333 10118 90710 91132== 201811091800 AAXX 09184 03301 16556 /1725 10103 20084 39771 49842 56066 60032 333 10127 82/32 87/50 90710 91141== 201811091800 AAXX 09184 03302 17550 /1533 10108 20089 39822 49835 56062 60032 782// 333 10127 55300 20000 82/28 87/48 91043 90710 91149== 201811091800 AAXX 09184 03305 17556 /2516 10097 20073 39616 49869 56053 60082 762// 333 10115 83/21 87/27 91037 90710 91144== 201811091800 AAXX 09184 03313 16861 /1415 10101 20081 39775 49866 57064 60012 333 10115 87/57 91029 90710 91129== 201811091800 AAXX 09184 03316 17669 /1320 10117 20071 39875 49885 58055 69902 757// 333 10122 83/37 87/57 91033 90710 91133== 201811091800 AAXX 09184 03318 16/// /1321 10105 20072 69942 333 10118 90710 91130== 201811091800 AAXX 09184 03321 17564 /1522 10113 20077 39879 49891 56054 69902 762// 333 10120 55300 20000 87/28 84/37 91032 90710 91132== 201811091800 AAXX 09184 03330 17580 /1516 10087 20062 39576 49928 58041 69922 781// 333 10095 86/20 83/61 91026 90710 91129== 201811091800 AAXX 09184 03344 15581 /1514 10086 20071 39618 49928 58043 69942 333 10090 81/21 87/61 91024== 201811091800 AAXX 09184 03346 16/// /1421 10084 20063 69942 333 10088 90710 91129== 201811091800 AAXX 09184 03351 165// /1619 10109 20070 39870 49911 58046 69922 333 10118 55300 20000 82/33 87/50 90710 91127== 201811091800 AAXX 09184 03354 15676 /1515 10104 20063 39815 49955 58032 69922 333 10109 55300 20000 84/49 87/62 91029 90710 91129== 201811091800 AAXX 09184 03373 16981 /1613 10099 20074 39898 49967 58026 60002 333 10109 82/64 83/72== 201811091800 AAXX 09184 03377 11/80 71516 10097 20073 39889 49971 58025 69902 70252 83072 333 10108 55300 20000 83364 87075== 201811091800 AAXX 09184 03379 16979 /1418 10096 20069 39896 49972 58026 69902 333 10109 85/64 85/69== 201811091800 AAXX 09184 03382 15980 /1512 10108 20078 39954 49963 56036 69902 333 10117 55300 20000 82/71== 201811091800 AAXX 09184 03385 46980 /1514 10101 20083 39971 49981 56029 333 10119 85/71== 201811091800 AAXX 09184 03391 11/81 71614 10104 20076 39972 49979 58024 69902 70262 85076 333 10116 85364 87270== 201811091800 AAXX 09184 03392 16973 /1622 10107 20085 39985 49989 58023 60002 333 10122 84/70 90710 91127== 201811091800 AAXX 09184 03405 16350 /1534 10097 20089 39731 49844 56056 60062 333 10109 55300 20000 81/09 86/17 85/38 91048 90710 91149== 201811091800 AAXX 09184 03409 16/// /1411 10098 20073 39682 49876 56058 60072 333 10114 55300 91024 90710 91129== 201811091700 AAXX 09174 03410 46468 /1413 10083 20065 39476 49899 58055 333 55300 20000 87/17 84/26 91025 90710 91130== 201811091800 AAXX 09184 03414 17564 /1520 10111 20078 39821 49907 56049 69902 781// 333 10118 55300 20000 87/29 91032 90710 91133== 201811091800 AAXX 09184 03462 15975 /1514 10105 20065 39885 49972 58026 69902 333 10116 55300 20000 87/63 85/67 85/71== 201811091800 AAXX 09184 03469 15981 /1615 10104 20080 39985 49989 58020 69902 333 10120 553// 20000 86/69== 201811091800 AAXX 09184 03482 15976 /1616 10110 20069 39978 40003 58016 60002 333 10126 87/70== 201811091800 AAXX 09184 03488 15981 /1615 10106 20085 39982 40008 56021 60002 333 10136 55300== 201811091800 AAXX 09184 03502 17450 /1526 10094 20094 39692 49849 55043 60112 762// 333 10109 55300 20000 82/10 86/32 91036 90710 91148== 201811091600 AAXX 09164 03503 47768 /1516 10106 20077 39824 49898 56065 781// 333 87/50 91027 90710 91132== 201811091800 AAXX 09184 03507 17426 /1726 10088 20080 39521 49882 57052 60072 763// 333 10103 86/11 84/36 91037 90710 91141== 201811091800 AAXX 09184 03520 16467 /1612 10104 20087 39794 49912 57048 60022 333 10119 55300 20000 82/16 87/22 91022 90710 91127== 201811091800 AAXX 09184 03522 17460 /1410 10104 20090 39826 49916 57049 60032 762// 333 10122 81/16 86/19 91021== 201811091800 AAXX 09184 03529 17562 /1519 10112 20081 39896 49938 58044 69922 782// 333 10127 83/28 86/33 90710 91128== 201811091800 AAXX 09184 03535 17564 /1515 10108 20073 39824 49938 57044 69982 781// 333 10116 553// 20000 84/28 85/36 91026 90710 91129== 201811091800 AAXX 09184 03544 15581 /1610 10110 20071 39826 49953 57039 69922 333 10119 553// 20000 86/31 84/38 91021 90710 91125== 201811091800 AAXX 09184 03560 15982 /1617 10105 20069 39877 49978 58032 69942 333 10122 553// 20000 87/61 86/68 90710 91127== 201811091800 AAXX 09184 03590 15977 /1712 10103 20070 39910 40018 58017 69922 333 10121 55300 20000 87/69== 201811091800 AAXX 09184 03604 16231 /1726 10122 20117 39793 49844 56039 60132 333 10124 82/06 85/16 91036 90710 91146== 201811091800 AAXX 09184 03605 16418 /1737 10113 20105 39865 49873 56045 60122 333 10127 86/11 84/19 91047 90710 91147== 201811091800 AAXX 09184 03609 16/// /1631 10126 20102 39832 49883 56055 60082 333 10130 91045 90710 91147== 201811091800 AAXX 09184 03647 16580 /1724 10100 20069 39697 49945 58041 60012 333 10110 553// 20000 85/23 86/30 90710 91132== 201811091800 AAXX 09184 03649 11575 81715 10114 20071 39857 49955 58040 60012 76062 8652/ 333 10125 55300 86630 87458 91026 90710 91126== 201811091800 AAXX 09184 03658 16681 /1523 10121 20065 39900 49968 56039 69902 333 10129 87/40 85/64 91033 90710 91136== 201811091800 AAXX 09184 03660 15676 /1613 10105 20063 39734 49976 56037 69922 333 10121 85/35 87/64 90710 91128== 201811091800 AAXX 09184 03672 11681 81615 10122 20063 39948 49987 58035 69922 70361 8152/ 333 10141 81635 87466== 201811091800 AAXX 09184 03680 16/// ///// 10109 20062 39834 49986 58032 69942 333 10122 553// 20000== 201811091800 AAXX 09184 03684 15981 /1512 10103 20069 39903 40007 58020 69922 333 10125 86/65== 201811091800 AAXX 09184 03693 15981 /1814 10113 20071 30018 40020 58021 69902 333 10130 55300 86/67== 201811091800 AAXX 09184 03707 17545 /1522 10116 20102 39881 49888 56046 60052 762// 333 10129 83/20 86/26 90710 91136== 201811091800 AAXX 09184 03710 16118 /1724 10088 20088 39492 49900 56049 60062 333 10096 55300 20000 87/03 86/10 91042 90710 91145== 201811091800 AAXX 09184 03716 17456 /1521 10114 20097 39838 49896 56056 60012 762// 333 10124 55300 20000 87/14 83/56 91035 90710 91137== 201811091800 AAXX 09184 03743 16447 /1613 10099 20084 39801 49958 56041 60022 333 10128 81/16 84/27 86/31 90710 91126== 201811091800 AAXX 09184 03746 17450 /1620 10099 20085 39812 49962 56041 60032 762// 333 10131 82/15 84/23 87/30 90710 91134== 201811091800 AAXX 09184 03749 16557 /1722 10106 20083 39857 49965 57040 60022 333 10134 87/27 84/42 90710 91135== 201811091800 AAXX 09184 03761 17663 /1621 10112 20073 39838 49978 57039 60012 781// 333 10128 55300 20000 81/39 85/47 91031 90710 91131== 201811091800 AAXX 09184 03768 16680 /1516 10123 20067 39905 49982 58038 69922 333 10134 81/39 84/49 86/66 90710 91126== 201811091800 AAXX 09184 03769 15675 /1712 10117 20067 39917 49997 58037 69982 333 10128 55300 20000 81/35 87/67== 201811091700 AAXX 09174 03770 46/// ///// 10119 20070== 201811091800 AAXX 09184 03772 15980 /1517 10120 20065 39959 49989 58035 69922 333 10141 55300 20000 88/67 90710 91125== 201811091800 AAXX 09184 03781 15981 /1611 10106 20064 39796 49998 58034 69962 333 10120 553// 20000 85/66 91021== 201811091800 AAXX 09184 03796 46/// /1818 10121 20086 39895 40034 58019 333 10129 91031 90710 91132== 201811091800 AAXX 09184 03797 15981 /1716 10118 20077 39975 40034 57022 60002 333 10131 55300 20000 87/69== 201811091800 AAXX 09184 03803 17758 /2324 10136 20134 39840 49876 53014 60102 723// 333 10137 83/50 90710 91130== 201811091800 AAXX 09184 03808 11250 82011 10119 20114 39772 49875 55022 60222 76062 885// 333 10131 55300 20000 82706 88657 90710 91129== 201811091800 AAXX 09184 03809 16463 /2116 10118 20114 39793 49882 55021 60142 333 10129 81/14 86/44 90710 91141== 201811091500 AAXX 09154 03823 47232 /1624 10099 20097 39689 49926 58059 762// 333 553// 20047 85/04 87/13 91044 90710 91144== 201811091600 AAXX 09164 03827 47420 /1627 10110 20102 39869 49930 58060 763// 333 83/12 84/20 86/23 91042 90710 91143== 201811091800 AAXX 09184 03840 17213 /1726 10096 20095 39619 49916 56049 60132 762// 333 10113 85/04 84/11 91045 90710 91148== 201811091800 AAXX 09184 03853 17456 /1626 10110 20096 39908 49931 56049 60052 762// 333 10131 55300 20000 82/15 86/25 90710 91139== 201811091800 AAXX 09184 03857 17521 /1638 10113 20106 39879 49941 58055 60052 762// 333 10136 87/20 91050 90710 91150== 201811091800 AAXX 09184 03862 17547 /1723 10111 20089 39952 49964 56043 60042 762// 333 10140 55300 20000 83/27 87/38 91038 90710 91139== 201811091800 AAXX 09184 03866 16/// /1921 10120 20081 39956 49980 56041 60012 333 10137 91034 90710 91135== 201811091800 AAXX 09184 03872 17658 /2024 10120 20092 39984 49989 58037 69942 781// 333 10138 553// 20000 84/34 84/47 91035 90710 91135== 201811091800 AAXX 09184 03876 16/// /1624 10136 20084 30000 40003 57037 69922 333 10139 91035 90710 91135== 201811091800 AAXX 09184 03882 15971 /1910 10120 20079 39958 40020 56028 69962 333 10135 55300 20000 88/68 90710 91125== 201811091800 AAXX 09184 03894 11458 81733 10107 20096 49964 57044 60042 76362 885// 333 10134 81614 83615 87620 91046 90710 91147== 201811091800 AAXX 09184 03895 17556 /1730 10109 20088 39882 49984 57039 60052 761// 333 10132 55300 20000 82/24 84/31 85/57 91045 90710 91147== 201811091800 AAXX 09184 03901 17784 /1509 10077 20069 39679 49764 55013 60162 723// 333 10102 55300 20000 87/50 90710 91131== 201811091800 AAXX 09184 03904 17762 /1511 10093 20079 39696 49754 56033 60152 782// 333 10107 87/50 90710 91126== 201811091600 AAXX 09164 03907 47757 /1430 10098 20082 39789 49796 56073 762// 333 55300 20018 87/50 91045 90710 91152== 201811091800 AAXX 09184 03915 17434 /1330 10100 20092 39703 49778 56054 60132 762// 333 10107 81/16 83/29 85/43 91050 90710 91150== 201811091800 AAXX 09184 03916 17230 /1720 10088 20083 39619 49802 56045 60122 763// 333 10105 553// 20000 85/06 86/15 91039 90710 91146== 201811091800 AAXX 09184 03917 17432 /1422 10099 20089 39721 49795 56048 60132 763// 333 10111 55300 20000 81/11 86/41 91032 90710 91141== 201811091800 AAXX 09184 03923 17356 /1824 10098 20094 39590 49778 56043 60252 762// 333 10100 82/08 86/42 91036 90710 91146== `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions