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 = '/Timestamp: (?<datetime>.+)[\r\n]+Message: (?<msg>[\s\S]*)[\r\n]+Category: (?<unparsed1>[\s\S]*)Machine: (?<instance>.*)[\r\n]+(?<unparsed2>[\s\S]+)/m'; $str = 'Timestamp: 10/06/2023 23:59:56.2329081 Message: Requests has exceeded the rate limit of 100/Minute. There were a total of 140 requests for clientId \'eb9f3c62-d0a5-4234-8dc0-ad6700d58eff\' from IP \'123.456.789.012\' on endpoint \'/Whatever/api/v1/blah\'. Time period started at 10/6/2023 11:59:23 PM and request was blocked at 10/6/2023 11:59:56 PM next line next line Category: Whatever EventId: 43122 Severity: Information Title: Machine: i-0ce037c69c9df1e33 Application Domain: /LM/W3SVC/1/ROOT/Whatever-1-133410567318541375 Process Id: 3860 Process Name: c:\\windows\\system32\\inetsrv\\w3wp.exe Win32 Thread Id: 2444 Thread Name: Extended Properties: '; preg_match_all($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