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

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/(?:[aeAE][lI][ -])?(?:[GKQ]h?|Qu)[aeu]([tdz]{1,2}[h\']?)\1?af{1,2}[iy]/'; $str = 'AI Kadafi Al Gaddafi Al Ghaddafi Al Qaddafi Al Qathafi Al-Gathafi Al-Kaddafi El Gaddafi El Kadhafi El Kazzafi El Qaddafi El Qathafi Gadaffi Gadafi Gadafy Gaddafi Gaddhafi Gadhafi Gathafi Ghadaffi Ghadafi Ghaddafi Ghaddafy Gheddafi Kad\'afi Kadaffi Kaddafi Kadhafi Kazzafi Khadaffy Khadafy Khaddafi Qadafi Qaddafi Qadhafi Qadhdhafi Qadthafi Qathafi Quathafi Qudhafi al Gaddafi al Ghaddafi al-Gaddafi al-Kad\'afi al-Kadafi al-Khaddafi al-Qadafi al-Qaddafi al-Qadhafi al-Qadhdhafi el Gaddafi el Gaddafy el Gadhafi el Qaddafi el-Gadhafi'; $subst = "\1\2\3\3\2\1"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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