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

/
/
gmx

Test String

Code Generator

Language

Generated Code

$re = '/( # start capture url (?:(?:(?:ht|f)tps?\:)\/\/?|(?:www\.)) # start with http or www (?:\s?[:\w?=%&+-]+ # need some chars in url, allow spaces. (?:(?:(?:\.)|(?:\/(?:\/)?)))? # can have ., / or // inside urls. )+ # allow repeat alternating pattern of chars and delimiters ) # end capture url/mx'; $str = 'http://www.apple.com/legal/ privacy/. abbbbbbbbbbbb abababab aaab hi h123213i.what let\'s do some URLs next segment> https://duckduckgo.com/?q=perl+regex+%2Fmxsp&t=canonical&atb=v143-1&ia=web, http://www.rexegg.com/regex-modifiers.html <segment hi there segment> https://duckduckgo.com/?q=tutorial+perl+regex+substitution+capture+groups&t=canonical&atb=v143-1&ia=web-https://regex101.com/, www.giggle.com B. Privacy Policy. At all times your information will be treated in accordance with Apple’s Privacy Policy, which is incorporated by reference into this License and can be viewed at: http://www.apple.com/legal/ privacy/. qweqweqwewqe www.howdy.com/welcome::&5'; preg_match_all($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