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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/(?:\/[a-z]{2})?\/[a-z]{2}[-_][a-z]{2}\b|\/(retail)\/[a-z]{2}\b/m'; $str = '/us/en_us/retail/en (matches /us/ and /us/en_us/) /us/en_us/retail (matches /us/ and /en_us/) /gb/en_gb/retail/en-uk (matches /en_gb and /en-uk) /us/en_us/retail/en /us/en_us/retail /gb/en_gb/retail/en-uk/ /us/en_us/e/retail/Ctral/Apps/jcr:content/par/expandableciner_57473905/image/file.img.png/1496964235.png /gb/retail/cowabunga /gb/en_gb/retail/en-uk /gb/en_gb/retail/en-uk/blah /de/de_de/retail/de_de/products/catalog /en-en/ab/cd'; $subst = "$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