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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

$re = '/<p><img .+ src="(.*?)" .+/m'; $str = '<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p> <p><img loading="lazy" class="wp-image-472983 size-large aligncenter" src="https://www.example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-1024x1024.jpg" alt="unsplash" width="1024" height="1024" srcset="http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-1024x1024.jpg 1024w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-300x300.jpg 300w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-150x150.jpg 150w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-768x768.jpg 768w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-1536x1536.jpg 1536w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-2048x2048.jpg 2048w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-480x480.jpg 480w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-280x280.jpg 280w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-1920x1920.jpg 1920w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-960x960.jpg 960w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-400x400.jpg 400w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-585x585.jpg 585w, http://example.com/wp-content/uploads/2021/02/giorgio-trovato-oqe33exyyuw-unsplash-45x45.jpg 45w" sizes="(max-width: 1024px) 100vw, 1024px" /></p> <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p> <p><img loading="lazy" class="alignnone wp-image-472988 size-large" src="https://www.example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-1024x683.jpg" alt="unsplash" width="1024" height="683" srcset="http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-1024x683.jpg 1024w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-300x200.jpg 300w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-150x100.jpg 150w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-768x512.jpg 768w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-1536x1024.jpg 1536w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-480x320.jpg 480w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-280x186.jpg 280w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-960x640.jpg 960w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-600x400.jpg 600w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920-585x390.jpg 585w, http://example.com/wp-content/uploads/2021/02/pickled-cucumbers-2201151_1920.jpg 1920w" sizes="(max-width: 1024px) 100vw, 1024px" /></p> '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php