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

/
/
g

Test String

Code Generator

Generated Code

$re = '/\b(?:(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9]))|\:(\d*)\b/'; $str = '<http>1.0.170.50:80</http> <http>1.1.189.58:8080</http> <http>1.1.220.100:8080</http> <http>1.2.252.65:8080</http> <http>1.20.166.142:8080</http> <http>1.32.59.217:47045</http> <http>1.179.136.98:8080</http> <http>1.179.144.41:8080</http> <http>1.179.148.9:36476</http> <http>1.186.85.38:1111</http> <http>3.20.236.208:49205</http> <http>3.215.177.148:49205</http> <http>5.16.0.97:1256</http> <http>5.16.0.174:8080</http> <http>5.16.0.180:8080</http> <http>5.16.1.17:8080</http> <http>5.22.196.30:8080</http> <http>5.44.62.166:8080</http> <http>5.58.33.187:55507</http> <http>5.59.145.129:8080</http> <http>5.135.176.161:10000</http> <http>5.153.234.91:3128</http> <http>5.180.130.90:80</http> <http>5.180.130.91:8080</http> <http>5.188.136.52:8080</http> <http>5.202.191.226:80</http> <http>8.242.207.202:8080</http> <http>12.88.29.66:9080</http> <http>12.144.254.185:9080</http> <http>12.218.209.130:13326</http> <http>14.102.13.161:8080</http>'; preg_match_all($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