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

/
/
gmi

Test String

Code Generator

Language

Generated Code

$re = '/^(?:(?:ds|crl|ocsp|dnl\-[0,1][0-9]\.geo|(?:[sp][0,1][0-9]|downloads)\.upd)\.kaspersky|downloads[0-9]?\.kaspersky\-labs)\.com$/mi'; $str = 'ds.kaspersky.com dnl-01.geo.kaspersky.com dnl-02.geo.kaspersky.com dnl-03.geo.kaspersky.com dnl-04.geo.kaspersky.com dnl-05.geo.kaspersky.com dnl-06.geo.kaspersky.com dnl-07.geo.kaspersky.com dnl-08.geo.kaspersky.com dnl-09.geo.kaspersky.com dnl-10.geo.kaspersky.com dnl-11.geo.kaspersky.com dnl-12.geo.kaspersky.com dnl-13.geo.kaspersky.com dnl-14.geo.kaspersky.com dnl-15.geo.kaspersky.com dnl-16.geo.kaspersky.com dnl-17.geo.kaspersky.com dnl-18.geo.kaspersky.com dnl-19.geo.kaspersky.com dnl-00.geo.kaspersky.com s00.upd.kaspersky.com s01.upd.kaspersky.com s02.upd.kaspersky.com s03.upd.kaspersky.com s04.upd.kaspersky.com s05.upd.kaspersky.com s06.upd.kaspersky.com s07.upd.kaspersky.com s08.upd.kaspersky.com s09.upd.kaspersky.com s10.upd.kaspersky.com s11.upd.kaspersky.com s12.upd.kaspersky.com s13.upd.kaspersky.com s14.upd.kaspersky.com s15.upd.kaspersky.com s16.upd.kaspersky.com s17.upd.kaspersky.com s18.upd.kaspersky.com s19.upd.kaspersky.com p00.upd.kaspersky.com p01.upd.kaspersky.com p02.upd.kaspersky.com p03.upd.kaspersky.com p04.upd.kaspersky.com p05.upd.kaspersky.com p06.upd.kaspersky.com p07.upd.kaspersky.com p08.upd.kaspersky.com p09.upd.kaspersky.com p10.upd.kaspersky.com p11.upd.kaspersky.com p12.upd.kaspersky.com p13.upd.kaspersky.com p14.upd.kaspersky.com p15.upd.kaspersky.com p16.upd.kaspersky.com p17.upd.kaspersky.com p18.upd.kaspersky.com p19.upd.kaspersky.com downloads.upd.kaspersky.com crl.kaspersky.com ocsp.kaspersky.com downloads.kaspersky-labs.com downloads0.kaspersky-labs.com downloads1.kaspersky-labs.com downloads2.kaspersky-labs.com downloads3.kaspersky-labs.com downloads4.kaspersky-labs.com downloads5.kaspersky-labs.com downloads6.kaspersky-labs.com downloads7.kaspersky-labs.com downloads8.kaspersky-labs.com downloads9.kaspersky-labs.com '; preg_match_all($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