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

/
/
gm

Test String

Code Generator

Generated Code

const regex = /(America\/Adak|America\/Anchorage|America\/Anguilla|America\/Antigua|America\/Araguaina|America\/Argentina\/Buenos_Aires|America\/Argentina\/Catamarca|America\/Argentina\/Cordoba|America\/Argentina\/Jujuy|America\/Argentina\/La_Rioja|America\/Argentina\/Mendoza|America\/Argentina\/Rio_Gallegos|America\/Argentina\/Salta|America\/Argentina\/San_Juan|America\/Argentina\/San_Luis|America\/Argentina\/Tucuman|America\/Argentina\/Ushuaia|America\/Aruba|America\/Asuncion|America\/Atikokan|America\/Bahia|America\/Bahia_Banderas|America\/Barbados|America\/Belem|America\/Belize|America\/Blanc-Sablon|America\/Boa_Vista|America\/Bogota|America\/Boise|America\/Cambridge_Bay|America\/Campo_Grande|America\/Cancun|America\/Caracas|America\/Cayenne|America\/Cayman|America\/Chicago|America\/Chihuahua|America\/Ciudad_Juarez|America\/Costa_Rica|America\/Coyhaique|America\/Creston|America\/Cuiaba|America\/Curacao|America\/Danmarkshavn|America\/Dawson|America\/Dawson_Creek|America\/Denver|America\/Detroit|America\/Dominica|America\/Edmonton|America\/Eirunepe|America\/El_Salvador|America\/Fort_Nelson|America\/Fortaleza|America\/Glace_Bay|America\/Goose_Bay|America\/Grand_Turk|America\/Grenada|America\/Guadeloupe|America\/Guatemala|America\/Guayaquil|America\/Guyana|America\/Halifax|America\/Havana|America\/Hermosillo|America\/Indiana\/Indianapolis|America\/Indiana\/Knox|America\/Indiana\/Marengo|America\/Indiana\/Petersburg|America\/Indiana\/Tell_City|America\/Indiana\/Vevay|America\/Indiana\/Vincennes|America\/Indiana\/Winamac|America\/Inuvik|America\/Iqaluit|America\/Jamaica|America\/Juneau|America\/Kentucky\/Louisville|America\/Kentucky\/Monticello|America\/Kralendijk|America\/La_Paz|America\/Lima|America\/Los_Angeles|America\/Lower_Princes|America\/Maceio|America\/Managua|America\/Manaus|America\/Marigot|America\/Martinique|America\/Matamoros|America\/Mazatlan|America\/Menominee|America\/Merida|America\/Metlakatla|America\/Mexico_City|America\/Miquelon|America\/Moncton|America\/Monterrey|America\/Montevideo|America\/Montserrat|America\/Nassau|America\/New_York|America\/Nome|America\/Noronha|America\/North_Dakota\/Beulah|America\/North_Dakota\/Center|America\/North_Dakota\/New_Salem|America\/Nuuk|America\/Ojinaga|America\/Panama|America\/Paramaribo|America\/Phoenix|America\/Port-au-Prince|America\/Port_of_Spain|America\/Porto_Velho|America\/Puerto_Rico|America\/Punta_Arenas|America\/Rankin_Inlet|America\/Recife|America\/Regina|America\/Resolute|America\/Rio_Branco|America\/Santarem|America\/Santiago|America\/Santo_Domingo|America\/Sao_Paulo|America\/Scoresbysund|America\/Sitka|America\/St_Barthelemy|America\/St_Johns|America\/St_Kitts|America\/St_Lucia|America\/St_Thomas|America\/St_Vincent|America\/Swift_Current|America\/Tegucigalpa|America\/Thule|America\/Tijuana|America\/Toronto|America\/Tortola|America\/Vancouver|America\/Whitehorse|America\/Winnipeg|America\/Yakutat)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(America\\\/Adak|America\\\/Anchorage|America\\\/Anguilla|America\\\/Antigua|America\\\/Araguaina|America\\\/Argentina\\\/Buenos_Aires|America\\\/Argentina\\\/Catamarca|America\\\/Argentina\\\/Cordoba|America\\\/Argentina\\\/Jujuy|America\\\/Argentina\\\/La_Rioja|America\\\/Argentina\\\/Mendoza|America\\\/Argentina\\\/Rio_Gallegos|America\\\/Argentina\\\/Salta|America\\\/Argentina\\\/San_Juan|America\\\/Argentina\\\/San_Luis|America\\\/Argentina\\\/Tucuman|America\\\/Argentina\\\/Ushuaia|America\\\/Aruba|America\\\/Asuncion|America\\\/Atikokan|America\\\/Bahia|America\\\/Bahia_Banderas|America\\\/Barbados|America\\\/Belem|America\\\/Belize|America\\\/Blanc-Sablon|America\\\/Boa_Vista|America\\\/Bogota|America\\\/Boise|America\\\/Cambridge_Bay|America\\\/Campo_Grande|America\\\/Cancun|America\\\/Caracas|America\\\/Cayenne|America\\\/Cayman|America\\\/Chicago|America\\\/Chihuahua|America\\\/Ciudad_Juarez|America\\\/Costa_Rica|America\\\/Coyhaique|America\\\/Creston|America\\\/Cuiaba|America\\\/Curacao|America\\\/Danmarkshavn|America\\\/Dawson|America\\\/Dawson_Creek|America\\\/Denver|America\\\/Detroit|America\\\/Dominica|America\\\/Edmonton|America\\\/Eirunepe|America\\\/El_Salvador|America\\\/Fort_Nelson|America\\\/Fortaleza|America\\\/Glace_Bay|America\\\/Goose_Bay|America\\\/Grand_Turk|America\\\/Grenada|America\\\/Guadeloupe|America\\\/Guatemala|America\\\/Guayaquil|America\\\/Guyana|America\\\/Halifax|America\\\/Havana|America\\\/Hermosillo|America\\\/Indiana\\\/Indianapolis|America\\\/Indiana\\\/Knox|America\\\/Indiana\\\/Marengo|America\\\/Indiana\\\/Petersburg|America\\\/Indiana\\\/Tell_City|America\\\/Indiana\\\/Vevay|America\\\/Indiana\\\/Vincennes|America\\\/Indiana\\\/Winamac|America\\\/Inuvik|America\\\/Iqaluit|America\\\/Jamaica|America\\\/Juneau|America\\\/Kentucky\\\/Louisville|America\\\/Kentucky\\\/Monticello|America\\\/Kralendijk|America\\\/La_Paz|America\\\/Lima|America\\\/Los_Angeles|America\\\/Lower_Princes|America\\\/Maceio|America\\\/Managua|America\\\/Manaus|America\\\/Marigot|America\\\/Martinique|America\\\/Matamoros|America\\\/Mazatlan|America\\\/Menominee|America\\\/Merida|America\\\/Metlakatla|America\\\/Mexico_City|America\\\/Miquelon|America\\\/Moncton|America\\\/Monterrey|America\\\/Montevideo|America\\\/Montserrat|America\\\/Nassau|America\\\/New_York|America\\\/Nome|America\\\/Noronha|America\\\/North_Dakota\\\/Beulah|America\\\/North_Dakota\\\/Center|America\\\/North_Dakota\\\/New_Salem|America\\\/Nuuk|America\\\/Ojinaga|America\\\/Panama|America\\\/Paramaribo|America\\\/Phoenix|America\\\/Port-au-Prince|America\\\/Port_of_Spain|America\\\/Porto_Velho|America\\\/Puerto_Rico|America\\\/Punta_Arenas|America\\\/Rankin_Inlet|America\\\/Recife|America\\\/Regina|America\\\/Resolute|America\\\/Rio_Branco|America\\\/Santarem|America\\\/Santiago|America\\\/Santo_Domingo|America\\\/Sao_Paulo|America\\\/Scoresbysund|America\\\/Sitka|America\\\/St_Barthelemy|America\\\/St_Johns|America\\\/St_Kitts|America\\\/St_Lucia|America\\\/St_Thomas|America\\\/St_Vincent|America\\\/Swift_Current|America\\\/Tegucigalpa|America\\\/Thule|America\\\/Tijuana|America\\\/Toronto|America\\\/Tortola|America\\\/Vancouver|America\\\/Whitehorse|America\\\/Winnipeg|America\\\/Yakutat)', 'gm') const str = `America/Adak America/Anchorage America/Anguilla America/Antigua America/Araguaina America/Argentina/Buenos_Aires America/Argentina/Catamarca America/Argentina/ComodRivadavia America/Argentina/Cordoba America/Argentina/Jujuy America/Argentina/La_Rioja America/Argentina/Mendoza America/Argentina/Rio_Gallegos America/Argentina/Salta America/Argentina/San_Juan America/Argentina/San_Luis America/Argentina/Tucuman America/Argentina/Ushuaia America/Aruba America/Asuncion America/Atikokan America/Atka America/Bahia America/Bahia_Banderas America/Barbados America/Belem America/Belize America/Blanc-Sablon America/Boa_Vista America/Bogota America/Boise America/Buenos_Aires America/Cambridge_Bay America/Campo_Grande America/Cancun America/Caracas America/Catamarca America/Cayenne America/Cayman America/Chicago America/Chihuahua America/Ciudad_Juarez America/Coral_Harbour America/Cordoba America/Costa_Rica America/Coyhaique America/Creston America/Cuiaba America/Curacao America/Danmarkshavn America/Dawson America/Dawson_Creek America/Denver America/Detroit America/Dominica America/Edmonton America/Eirunepe America/El_Salvador America/Ensenada America/Fort_Nelson America/Fort_Wayne America/Fortaleza America/Glace_Bay America/Godthab America/Goose_Bay America/Grand_Turk America/Grenada America/Guadeloupe America/Guatemala America/Guayaquil America/Guyana America/Halifax America/Havana America/Hermosillo America/Indiana/Indianapolis America/Indiana/Knox America/Indiana/Marengo America/Indiana/Petersburg America/Indiana/Tell_City America/Indiana/Vevay America/Indiana/Vincennes America/Indiana/Winamac America/Indianapolis America/Inuvik America/Iqaluit America/Jamaica America/Jujuy America/Juneau America/Kentucky/Louisville America/Kentucky/Monticello America/Knox_IN America/Kralendijk America/La_Paz America/Lima America/Los_Angeles America/Louisville America/Lower_Princes America/Maceio America/Managua America/Manaus America/Marigot America/Martinique America/Matamoros America/Mazatlan America/Mendoza America/Menominee America/Merida America/Metlakatla America/Mexico_City America/Miquelon America/Moncton America/Monterrey America/Montevideo America/Montreal America/Montserrat America/Nassau America/New_York America/Nipigon America/Nome America/Noronha America/North_Dakota/Beulah America/North_Dakota/Center America/North_Dakota/New_Salem America/Nuuk America/Ojinaga America/Panama America/Pangnirtung America/Paramaribo America/Phoenix America/Port-au-Prince America/Port_of_Spain America/Porto_Acre America/Porto_Velho America/Puerto_Rico America/Punta_Arenas America/Rainy_River America/Rankin_Inlet America/Recife America/Regina America/Resolute America/Rio_Branco America/Rosario America/Santa_Isabel America/Santarem America/Santiago America/Santo_Domingo America/Sao_Paulo America/Scoresbysund America/Shiprock America/Sitka America/St_Barthelemy America/St_Johns America/St_Kitts America/St_Lucia America/St_Thomas America/St_Vincent America/Swift_Current America/Tegucigalpa America/Thule America/Thunder_Bay America/Tijuana America/Toronto America/Tortola America/Vancouver America/Virgin America/Whitehorse America/Winnipeg America/Yakutat America/Yellowknife `; // 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