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

/
/
g

Test String

Code Generator

Language

Generated Code

$re = '/(?:([A-Za-z]+):\/\/)?(?:([A-Za-z0-9]+)\:([A-Za-z0-9]+)\@)?((?:[A-Za-z0-9]+\.)+[A-Za-z0-9]+)(?:\:([0-9]+))?(?:\/((?:[A-Za-z0-9]+)(?:\/[A-Za-z0-9]+)*(?:\.[A-Za-z0-9]+)?)?(\?[A-Za-z0-9]+=[A-Za-z0-9]+(?:&[A-Za-z0-9]+=[A-Za-z0-9]+)*)?(?:#([A-Za-z0-9]+))?)?/'; $str = 'http://root:123@google.com:80/search/wtf?qqqq=123&www=456#result http://google.com/page/page.html http://www.google.com/page?qqqq=123 omg.wtf.google.com/page/page.wtf?qqqq=123&eee=455&4444=445 lol.com/page#anchor lol.com/page.php#ancohr wtf.omg/?param=value wtf.omg/#anchor root:123@myhost.org/page.php#anchor root:123@wtf.omg.lol.com/?param=233#anchor'; preg_match_all($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