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 = /(?'DateTime'\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}).*INFO *....(?'TaskName'\w+).*KMR200_(?'MR'\d).*Target Name: (?'TargetName'\w+\-\w+)\n.*Target Type\: (?'TargetType'\w+)\n.*Cycle Time: (?'CycleTime'\d+.\d+)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?\'DateTime\'\\d{4}-\\d{2}-\\d{2} \\d{2}:\\d{2}:\\d{2}).*INFO *....(?\'TaskName\'\\w+).*KMR200_(?\'MR\'\\d).*Target Name: (?\'TargetName\'\\w+\\-\\w+)\\n.*Target Type\\: (?\'TargetType\'\\w+)\\n.*Cycle Time: (?\'CycleTime\'\\d+.\\d+)', 'gm') const str = `2018-09-03 15:01:58,384 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 24.178 seconds 2018-09-03 15:01:59,934 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-11 2018-09-03 15:01:59,934 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:02:21,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.952 seconds 2018-09-03 15:06:52,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-16 2018-09-03 15:06:52,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:07:27,960 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 35.298 seconds 2018-09-03 15:10:16,361 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BPRD26-1 2018-09-03 15:10:16,361 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: TOOL 2018-09-03 15:10:41,524 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 25.179 seconds 2018-09-03 15:14:42,750 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-1 2018-09-03 15:14:42,750 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:15:06,262 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 23.523 seconds 2018-09-03 15:17:25,399 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-6 2018-09-03 15:17:25,399 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:17:46,641 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.258 seconds 2018-09-03 15:21:22,709 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-2 2018-09-03 15:21:22,709 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:21:43,892 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.194 seconds 2018-09-03 15:26:42,393 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-7 2018-09-03 15:26:42,393 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:27:06,475 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 24.093 seconds 2018-09-03 15:28:29,608 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-5 2018-09-03 15:28:29,608 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:01:58,384 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 24.178 seconds 2018-09-03 15:01:59,934 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-11 2018-09-03 15:01:59,934 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:02:21,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.952 seconds 2018-09-03 15:06:52,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-16 2018-09-03 15:06:52,873 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:07:27,960 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 35.298 seconds 2018-09-03 15:10:16,361 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BPRD26-1 2018-09-03 15:10:16,361 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: TOOL 2018-09-03 15:10:41,524 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 25.179 seconds 2018-09-03 15:14:42,750 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-1 2018-09-03 15:14:42,750 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:15:06,262 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 23.523 seconds 2018-09-03 15:17:25,399 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-6 2018-09-03 15:17:25,399 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:17:46,641 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.258 seconds 2018-09-03 15:21:22,709 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-2 2018-09-03 15:21:22,709 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:21:43,892 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 21.194 seconds 2018-09-03 15:26:42,393 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-7 2018-09-03 15:26:42,393 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK 2018-09-03 15:27:06,475 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] PickTask: Cycle Time: 24.093 seconds 2018-09-03 15:28:29,608 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Name: BSK270M1-5 2018-09-03 15:28:29,608 INFO [...PickTask@KMR200_6_Semiconductor_Fab_200] Target Type: ERACK `; // 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