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

Code Generator

Language

Generated Code

$re = '/^:(?![^:]*([^:])[^:]*\1)[dgimsuy]{0,7}:$/m'; $str = ':: :g: :d: :i: :m: :s: :u: :y: :dg: :gi: :ms: :uy: :sd: :mu: :yi: :dgi: :gms: :iuy: :sdm: :ymu: :dgim: :gims: :iysu: :msuy: :dgims: :gimsu: :iysum: :mugsy: :dsygiu: :gsiumd: :ydsugi: :isgumy: :mugydi: :ysgmdi: :sgydmi: :yigdsm: :mudysg: :gsdiuy: :digmsuy: :sudgimy: :ydugsim: :mudyisg: :sgimydu: :ysgidum: :muidsyg: :gusdymi: :yidgums: :sugmidy: :gg: :dd: :ii: :mm: :ss: :uu: :yy: :dgg: :idd: :iig: :mmm: :sms: :uuu: :yyy: :dggi: :iddd: :iigm: :mmmm: :smss: :uuuu: :yyyy: :dggiu: :idddm: :iigmy: :mmmms: :smsss: :uuuuy: :yyyym: :dgimsguy: :ydsgimuy: :dgimsuyy:'; preg_match_all($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