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

/
/
gi

Test String

Code Generator

Generated Code

const regex = /\/wp-content\/themes\//gi; // Alternative syntax using RegExp constructor // const regex = new RegExp('\\\/wp-content\\\/themes\\\/', 'gi') const str = `0 = /path/to/file/index.php 1 = /path/to/file/wp-blog-header.php 2 = /path/to/file/wp-load.php 3 = /path/to/file/wp-config.php 4 = /path/to/file/wp-settings.php 5 = /path/to/file/wp-includes/load.php 6 = /path/to/file/wp-includes/default-constants.php 7 = /path/to/file/wp-includes/version.php 8 = /path/to/file/wp-includes/compat.php 9 = /path/to/file/wp-includes/functions.php 10 = /path/to/file/wp-includes/option.php [...] 219 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/page_link.php 220 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/post_object.php 221 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/relationship.php 222 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/taxonomy.php 223 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/user.php 224 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/date_picker/date_picker.php 225 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/color_picker.php 226 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/message.php 227 = /path/to/file/wp-content/plugins/advanced-custom-fields/core/fields/tab.php 228 = /path/to/file/wp-content/plugins/add-to-any/add-to-any-wp-widget.php 229 = /path/to/file/wp-includes/class-wp-admin-bar.php 230 = /path/to/file/wp-includes/template-loader.php 231 = /path/to/file/wp-content/themes/themename/category.php 232 = /path/to/file/wp-content/themes/themename/header.php 233 = /path/to/file/wp-content/themes/themename/content.php 234 = /path/to/file/wp-content/themes/themename/sidebar.php 235 = /path/to/file/wp-content/themes/themename/footer.php`; // 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