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 = /(?:(\$.*):)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?:(\\$.*):)', 'gm') const str = `\$application-background: rgba(81, 99, 120, 0.1); \$application-background-light: #ffffff; \$primary-light: #00a6ff; // rgba(0, 166, 255, 1) \$primary-light-accent: #1f95f8; \$primary-lighter: #99dcff; \$primary-dark: #36436b; // rgba(54, 67, 107, 1) \$primary-darker: #2b3555; \$primary-darkest: #191f32; \$secondary-light: #008aff; \$tertiary-light: #4f5bff; \$quaternary-light: #27358c; \$sub-accent1: #00ea42; \$sub-accent2: #bedb00; \$sub-accent3: #ffb428; \$widget-light: #f3f4f6; \$widget-lightest: #ffffff; \$widget-disabled-light: #ccc; \$widget-disabled-lighter: #f9f9f9; \$navbar-color-default: \$widget-lightest; \$navbar-light-color: #fafafa; \$sidebar-background: #fafafa; \$text-light: #516378; \$text-lighter: #889aae; \$text-lightest: #cccccc; \$text-dark: #ffffff; \$text-dark2: #efefef; \$text-darker: #dedede; \$text-disabled: \$text-lightest; \$text-placeholder-dark: \$text-dark2; \$text-navbar-bright: rgba(0, 0, 0, 0.9); \$text-navbar-bright2: rgba(0, 0, 0, 0.4); \$text-navbar-dark: rgba(255, 255, 255, 1); \$text-navbar-dark2: rgba(255, 255, 255, 0.4); \$border-light: #e8ebed; \$border-dark: #ccc; \$border-active: \$text-light; \$border-color-dark: #d9d9d9 \$border-dark #b3b3b3; \$warning: #ffa908; \$trend-high: #ff3d79; \$trend-low: #1e98ff; \$trend-mid: \$text-light; \$list-item-selected: rgba(81, 99, 120, 0.2); \$list-item-hover: rgba(81, 99, 120, 0.1); \$poor: #ff7da5; \$fair: #ffafc8; \$average: #ffdfa4; \$good: #a1d525; \$excellent: #00d63d; :export { primaryDark: \$primary-dark; primaryLight: \$primary-light; secondaryLight: \$secondary-light; tertiaryLight: \$tertiary-light; quaternaryLight: \$quaternary-light; subAccent1: \$sub-accent1; subAccent2: \$sub-accent2; subAccent3: \$sub-accent3; poor: \$poor; fair: \$fair; average: \$average; good: \$good; excellent: \$excellent; } \$black: black; \$black-10: rgba(0, 0, 0, .1); \$black-15: rgba(0, 0, 0, .15); \$black-20: rgba(0, 0, 0, .2); \$black-30: rgba(0, 0, 0, .3); \$black-40: rgba(0, 0, 0, .4); \$darker: #152128; \$darker-40: rgba(21, 32, 40, .4); // rgba(\$darker, .4) \$darker-50: rgba(21, 32, 40, .5); // rgba(\$darker, .5) \$darker-70: rgba(21, 32, 40, .7); // rgba(\$darker, .7) \$darker-80: rgba(21, 32, 40, .8); // rgba(\$darker, .8) \$darker-90: rgba(21, 32, 40, .9); // rgba(\$darker, .9) \$dark-two-10: rgba(81, 99, 120, .1); \$dark-two-20: rgba(81, 99, 120, .2); \$dark: #516378; \$dark-60: rgba(81, 99, 120, .6); \$dark-10: rgba(81, 99, 120, .1); // rgba(80, 99, 120, .1) rgba(81, 99, 119, .1) \$dark-15: rgba(81, 99, 120, .15); \$dark-30: rgba(81, 99, 120, .3); \$dark-20: rgba(81, 99, 120, .2); // rgba(80, 99, 120, .2) rgba(81, 99, 119, .2) \$dark-40: rgba(81, 99, 120, .4); \$dark-6: rgba(81, 99, 120, .06); \$gray: #7C858C; \$light: #98A7B3; // #97A7B4 #97A6B2 \$light-50: rgba(152, 166, 179, .5); \$lighter: #E8EBED; \$smooth-sky: #87D5FF; \$sky: #00E2F5; \$sky-20: rgba(0, 221, 244, .2); \$magenta: #FF21A3; \$magenta-10: rgba(255, 33, 163, .1); \$yellow: #FFB000; // #FFA908 \$lemon: #EDED00; \$spring: #4BFF6B; \$green: #00D63D; \$cobalt: #00A6FF; \$cobalt-10: rgba(0, 195, 255, .1); // rgba(0, 165, 255, .1) \$cobalt-20: rgba(0, 195, 255, .2); \$blue: #4A4FEB; \$purple: #9270FF; \$navy: #1B1464; \$snow: #F3F4F5; // #F2F2F2 \$snow-68: rgba(243, 244, 245, .68); \$pale-grey-five: #F5F5F7; \$snow-60: rgba(243, 244, 245, .6); // rgba(243, 243, 244, .6) \$warm-grey-10: rgba(119, 119, 119, .1); \$white: white; \$white-30: rgba(255, 255, 255, .3); \$white-50: rgba(255, 255, 255, .5); \$white-70: rgba(255, 255, 255, .7); \$midnight: #36436B; \$midnight-hover: #2B3457; \$dawn: #5B83FE; \$dawn-hover: #4864CD; \$periwinkle: #A98FFF; \$pastel-purple: #B7A1FF; \$carolina-blue: #87A5FF; \$pastel-blue: #9DB5FE; \$pale-grey: #EEF1F4; \$warm-pink: #FF3D79; \$warm-pink-darker: #e6376e; \$warm-pink-darkest: #c22f5d; \$warm-pink-15: rgba(255, 61, 121, .15); \$pale-grey-two: #E8EBED; \$pale-grey-two-50: rgba(232, 235, 237, .5); \$pale-grey-two-30: rgba(232, 235, 237, .3); \$pale-grey-two-70: rgba(232, 235, 237, .7); \$pale-grey-two-20: rgba(232, 235, 237, .2); \$pale-grey-two-10: rgba(232, 235, 237, .1); \$pale-grey-three: #EAEFF4; \$charcoal-grey: #2B2F35; \$charcoal-grey-80: rgba(43, 47, 43, .8); // rgba(42, 47, 52, .8) \$charcoal-grey-90: rgba(43, 47, 43, .9); // rgba(43, 47, 52, .9) \$charocol-grey-30: rgba(43, 47, 53, .3); \$silver: #DCE0E4; // #CFD2D4 #C9D0D5 \$silver-two: #D2DADF; \$silver-three: #C9D0D5; \$azure: #00A6FF; \$azure-two: #0095E4; \$azure-hover: #008AD4; \$watermelon: #FF4168; \$light-30: rgba(152, 166, 179, .3); \$light-70: rgba(152, 166, 179, .7); \$cerulean: #007DC0; \$wheat: #FFD37E; \$off-white-two: #FFF6E1; \$pale-peach-two: #FFDEAD; \$ice-blue: #ECF9FF; \$pale-sky-blue: #B7E7FF; \$slate: #516272; \$bluey-grey: #97A6B2; \$bluey-grey-two: #98A7B3; \$bluey-grey-three: #A7B6C2; \$slate-three: #405064; \$slate-two: #404F5F; \$silver-four: #DEE1E4; \$silver-five: #D9DCDF; \$coral-pink: #FF5771; \$silver-six: #C0C9D0; \$sky-blue: #5CC7FF; :export { dark: \$dark; dark10: \$dark-10; dark20: \$dark-20; } // not registered in zeplin \$warm-dark: #404F5F; // #435262 \$warm-dark-40: rgba(64, 79, 95, .4); // rgba(64, 80, 101, .4) \$soft-sky: #8FD8FF; \$charcoal-grey-two: #2F343A; \$azure-three: #00C3FF; \$deep-green: #00A02E; \$sun-yellow: #F5E11F; \$cadet-blue: #52689D; \$greenblue: #00D175; \$greenblue-two: #00B07F; \$light-sky-blue: #CCF3FF; \$event-header: #EDEFF0; // react table \$tr-group-border: rgba(0, 0, 0, .05); // shop AB funnel page \$resource-a: #7ab8fc; \$resource-b: #86919f; :export { resourceA: \$resource-a; resourceB: \$resource-b; } `; // 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