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

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /^([\s]{2,})(?!.*[&@])(.*?)([,{])\n/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^([\\s]{2,})(?!.*[&@])(.*?)([,{])\\n', 'gm') const str = `#term-header { padding: 20px 0 17px; margin: 0 10px 30px; &::before, &::after { margin-left: -11px; border-width: 12px 10.5px 0 10.5px; } &::before { bottom: -12px; } &::after { bottom: -10px; } h1 { font-size: 20px; span { font-size: 27px; } } dl { margin: 20px 0 0; dt { width: 100px; } dd { font-size: 11px; } } } .slick-next, .slick-prev { width: 35px; height: 35px; } .slick-prev { left: 5px; transform: translate3d(-30px, 0, 0); &::after { left: 14px; } } .slick-next { right: 5px; transform: translate3d(30px, 0, 0); &::after { right: 14px; } } .ready.inview { .slick-prev { &.slick-disabled { transform: translate3d(-30px, 0, 0); } } .slick-next { &.slick-disabled { transform: translate3d(30px, 0, 0); } } } .wp-editor { font-family: var(--fontFamily); font-size: var(--fontSize); line-height: var(--lineHeight); & h3, & h4, & p { margin: var(--wpEditorMargin) 0; overflow: hidden; &:first-child { margin-top: 0; } &:last-child { margin-bottom: 0; } } & h3 { font-size: 14px; } & h4 { font-size: 13px; } & a { color: var(--linkColor); text-decoration: underline; &:hover { text-decoration: none; } } & img { max-width: 100%; height: auto; } & blockquote { padding-left: 15px; margin: var(--wpEditorMargin) 0; font-weight: bold; border-left: 5px solid var(--borderColor); @media (--viewport-medium) { padding-left: 35px; } } }`; // 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