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 = /(?i)(?<=")\s*(?:https?)?:\/\/[^"]+\/(?=[^"]*logo)[^"]*(?:png|jpe?g|gif|tiff)\s*(?=")/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?i)(?<=")\\s*(?:https?)?:\\\/\\\/[^"]+\\\/(?=[^"]*logo)[^"]*(?:png|jpe?g|gif|tiff)\\s*(?=")', 'gm') const str = `<link rel="icon" href="https://diabsolut.com/wp-content/uploads/2018/02/D-Logo-150x150.png" sizes="32x32"> <link rel="icon" href="https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png" sizes="192x192"> <link rel="apple-touch-icon-precomposed" href="https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png"> <meta name="msapplication-TileImage" content="https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png"> <img width="200" height="147" src="https://diabsolut.com/wp-content/uploads/2017/05/Diabsolut-logo-01-e1496083111444.png" class="attachment-large size-large" alt=""> <img src="https://diabsolut.com/wp-content/uploads/2019/03/White-FSM-logo.png" width="330" height="215" data-no-retina="" style=""> <img src="https://diabsolut.com/wp-content/uploads/2017/05/Diabsolut-Cloud-Logo-Web-1.png" width="277" height="81" data-no-retina="" style="height: 100%; width: 100%; text-align: left; line-height: 16px; letter-spacing: 0px; font-weight: 300; font-size: 12px; border-color: rgb(255, 255, 255); border-style: none; margin: 0px; border-radius: 0px; padding: 0px;" data-stylerecorder="true"> <img width="300" height="179" src="https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo-300x179.png" class="attachment-medium size-medium" alt="" srcset="https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo-300x179.png 300w, https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo.png 350w" sizes="(max-width: 300px) 100vw, 300px"></a></div><h4 style="text-align: center" class="vc_custom_heading vc_custom_1508180231294">Consulting Solutions</h4> logout`; // 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