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

/
/

Test String

Code Generator

Language

Generated Code

$re = '/(?:RTDM_Thread_Pool)",(?:"\w+":"[0-9A-Za-z-_]{1,}",){1,}"__value_string__":"[^"]+?metric=\'(rtmsasrtdm01.\w+ActiveThreads)/'; $str = '{"annotations":{"DominosAlarm":"RTDM_Thread_Pool","__alertId__":"72","__alertScreenshotToken__":"d011471d-3947-409b-8ea4-d74bfb288d11","__dashboardUid__":"Do8Yh3jmk","__panelId__":"2","__value_string__":"[ var=\'A2\' metric=\'rtmcrtsasrtdm01.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A3\' metric=\'rtmcrtsasrtdm01.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A4\' metric=\'rtmcrtsasrtdm01.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A5\' metric=\'rtmcrtsasrtdm02.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A6\' metric=\'rtmcrtsasrtdm02.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A7\' metric=\'rtmcrtsasrtdm02.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A8\' metric=\'rtminfsasrtdm01.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A9\' metric=\'rtminfsasrtdm01.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A10\' metric=\'rtminfsasrtdm01.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A11\' metric=\'rtminfsasrtdm02.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A12\' metric=\'rtminfsasrtdm02.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A13\' metric=\'rtminfsasrtdm02.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A14\' metric=\'rtmsasrtdm01.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A15\' metric=\'rtmsasrtdm01.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A16\' metric=\'rtmsasrtdm01.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A17\' metric=\'rtmsasrtdm02.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A18\' metric=\'rtmsasrtdm02.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A19\' metric=\'rtmsasrtdm02.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A20\' metric=\'rtmsasrtdm03.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A21\' metric=\'rtmsasrtdm03.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A22\' metric=\'rtmsasrtdm03.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A23\' metric=\'rtmsasrtdm04.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A24\' metric=\'rtmsasrtdm04.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A25\' metric=\'rtmsasrtdm04.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A26\' metric=\'rtmsasrtdm05.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A27\' metric=\'rtmsasrtdm05.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A28\' metric=\'rtmsasrtdm05.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A29\' metric=\'rtmsasrtdm06.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A30\' metric=\'rtmsasrtdm06.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A31\' metric=\'rtmsasrtdm06.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A32\' metric=\'NoData\' labels={} value=null ]"},"endsAt":"2022-08-15T14:51:09.011+03:00","fingerprint":"07a1142e17b266ce","receivers":[{"name":"autogen-contact-point-default"}],"startsAt":"2022-08-15T14:48:09.011+03:00","status":{"inhibitedBy":[],"silencedBy":[],"state":"active"},"updatedAt":"2022-08-15T14:48:15.951+03:00","generatorURL":"http://rtmsasanalys01.msk.mts.ru:3000/alerting/grafana/UzwGQ2kVz/view","labels":{"Trigger":"[ var=\'A0\' metric=\'NoData\' labels={} value=null ], [ var=\'A1\' metric=\'NoData\' labels={} value=null ], [ var=\'A2\' metric=\'rtmcrtsasrtdm01.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A3\' metric=\'rtmcrtsasrtdm01.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A4\' metric=\'rtmcrtsasrtdm01.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A5\' metric=\'rtmcrtsasrtdm02.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A6\' metric=\'rtmcrtsasrtdm02.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A7\' metric=\'rtmcrtsasrtdm02.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A8\' metric=\'rtminfsasrtdm01.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A9\' metric=\'rtminfsasrtdm01.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A10\' metric=\'rtminfsasrtdm01.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A11\' metric=\'rtminfsasrtdm02.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A12\' metric=\'rtminfsasrtdm02.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A13\' metric=\'rtminfsasrtdm02.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A14\' metric=\'rtmsasrtdm01.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A15\' metric=\'rtmsasrtdm01.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A16\' metric=\'rtmsasrtdm01.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A17\' metric=\'rtmsasrtdm02.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A18\' metric=\'rtmsasrtdm02.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A19\' metric=\'rtmsasrtdm02.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A20\' metric=\'rtmsasrtdm03.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A21\' metric=\'rtmsasrtdm03.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A22\' metric=\'rtmsasrtdm03.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A23\' metric=\'rtmsasrtdm04.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A24\' metric=\'rtmsasrtdm04.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A25\' metric=\'rtmsasrtdm04.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A26\' metric=\'rtmsasrtdm05.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A27\' metric=\'rtmsasrtdm05.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A28\' metric=\'rtmsasrtdm05.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A29\' metric=\'rtmsasrtdm06.ActivityThreadPool_ActiveThreads\' labels={} value=null ], [ var=\'A30\' metric=\'rtmsasrtdm06.JdbcOracle_ActiveThreads\' labels={} value=null ], [ var=\'A31\' metric=\'rtmsasrtdm06.JdbcSastkts_ActiveThreads\' labels={} value=null ], [ var=\'A32\' metric=\'NoData\' labels={} value=null ]","__alert_rule_uid__":"UzwGQ2kVz","alertname":"RTDM Thread Pool alert","rule_uid":"UzwGQ2kVz"}}'; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($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