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

const regex = /^(?<longtime>[^ ]+\s[^ ]+)\s\[(?<thread>[^\]]+)\]\s\[(?<loglevel>[A-Z]+)(?>[^\(]+)\((?<process>[^\)]+)\)\s+(?<message>.+)$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?<longtime>[^ ]+\\s[^ ]+)\\s\\[(?<thread>[^\\]]+)\\]\\s\\[(?<loglevel>[A-Z]+)(?>[^\\(]+)\\((?<process>[^\\)]+)\\)\\s+(?<message>.+)$', 'gm') const str = `2019-06-05 09:35:43,001 [http-bio-8080-exec-4278] [ERROR] (o.a.r.v.i.MavenMetadataInterceptor:175) - IO exception retrieving maven metadata content from repo 'codehaus': Failed to parse metadata: end tag name </head> must be the same as start tag <meta> from line 25 (position: TEXT seen ... maximum-scale=1.0; user-scalable=0;" name="viewport">\\n </head>... @26:12) . 2019-06-04 15:36:16,981 [http-bio-8080-exec-4248] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-release-local:org/sonarsource/scanner/maven/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:16,981 [http-bio-8080-exec-4254] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-release-local:com/spotify/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:16,981 [http-bio-8080-exec-4236] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-snapshot-local:com/spotify/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:16,982 [http-bio-8080-exec-4256] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-snapshot-local:org/sonarsource/scanner/maven/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:17,024 [http-bio-8080-exec-4237] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-release-local:org/codehaus/mojo/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:17,024 [http-bio-8080-exec-4238] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-snapshot-local:org/apache/maven/plugins/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:17,025 [http-bio-8080-exec-4216] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-release-local:org/apache/maven/plugins/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:17,026 [http-bio-8080-exec-4257] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-snapshot-local:org/codehaus/mojo/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:17,071 [http-bio-8080-exec-4213] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-snapshot-local:org/sonarsource/scanner/maven/sonar-maven-plugin/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:17,072 [http-bio-8080-exec-4251] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-release-local:org/sonarsource/scanner/maven/sonar-maven-plugin/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:19,116 [http-bio-8080-exec-4242] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-snapshot-local:org/apache/maven/plugins/maven-compiler-plugin/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:19,116 [http-bio-8080-exec-4248] [WARN ] (o.a.r.ArtifactoryResponseBase:105) - Sending HTTP error code 403: Download request for repo:path 'ext-release-local:org/apache/maven/plugins/maven-compiler-plugin/maven-metadata.xml' is forbidden for user 'gispa-service-r00'. 2019-06-04 15:36:40,714 [art-exec-3128064] [INFO ] (o.a.s.a.ArchiveIndexerImpl:147) - Indexing archive: libs-snapshot-local:ru/russianpost/gispa/aps/appeals-boot/1.3.11-SNAPSHOT/appeals-boot-1.3.11-20190604.123558-2.jar 2019-06-04 15:36:41,094 [art-exec-3128064] [INFO ] (o.a.s.a.ArchiveIndexerImpl:147) - Indexing archive: libs-snapshot-local:ru/russianpost/gispa/aps/appeals-boot/1.3.11-SNAPSHOT/appeals-boot-1.3.11-20190604.123558-2-sources.jar 2019-06-04 15:36:41,112 [art-exec-3128064] [INFO ] (o.a.s.a.ArchiveIndexerImpl:147) - Indexing archive: libs-snapshot-local:ru/russianpost/gispa/aps/appeals-boot/1.3.11-SNAPSHOT/appeals-boot-1.3.11-20190604.123558-2-javadoc.jar 2019-06-04 15:36:41,140 [art-exec-3128064] [INFO ] (o.a.s.a.ArchiveIndexerImpl:147) - Indexing archive: libs-snapshot-local:ru/russianpost/gispa/aps/appeals-boot/1.3.11-SNAPSHOT/appeals-boot-1.3.11-20190604.123558-2-docker-info.jar`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions