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 = /Tapper\s*(\d*(?:\.\d+)?)[\s\S]*?M845/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('Tapper\\s*(\\d*(?:\\.\\d+)?)[\\s\\S]*?M845', 'gm') const str = `% N1 ( POSTED FILE NAME - WORKNC POST ) N2 ( INPUT FILE NAME - _6033_Cavity__01.TBA) N3 (DATE/TIME: Thu Mar 15 06:36:08 2018) N4 G0 G40 G80 G90 G98 N5 G17 N6 G57H901 N7 G173W0.0 N8 B0.000 N9 (Tapper 0.250000) N10 T21 N11 M06 N12 S100 N13 M843 N14 G173 W0.0 N15 (- ) N16 ( Tapping ) N17 G0 G90 X-0.0001 Y8.8135 N18 G43 Z10.0632 H21 N19 G01 F500. X-0.0001 Y8.8135 N20 G01 Z9.7163 F500. N21 G98 G84 X-0.0001 Y8.8135 Z6.0376 R7.6376 E10. N22 G80 G01 F500. N23 X-0.0001 Y8.8135 Z9.7163 N24 X-0.0001 Y8.8135 Z9.7163 N25 N26 M845 N27 G91 G28 Z0 N28 G90 N29 G57H901 N30 G173W0.0 N31 B0.000 N32 (Drill 0.005000) N33 T19 N34 M06 N35 S5000 N36 M3 N37 G173 W0.0 N38 (- ) N39 ( Contour Chamfer ) N40 G0 G90 X-0.0001 Y8.8135 N41 G43 Z9.7163 H19 N42 Z7.6375 N43 G01 Z9.8376 F500. N44 X-0.0001 Y8.8135 Z10.0632 N45 N46 M05 N47 G91 G28 Z0 N48 G90 N49 G57H901 N50 G173W0.0 N51 B0.000 N52 (Tapper 0.750000) N53 T21 N54 M06 N55 S100 N56 M843 N57 G173 W0.0 N58 (- ) N59 ( Tapping ) N60 G0 G90 X-0.0001 Y8.8135 N61 G43 Z10.0632 H21 N62 G01 F500. X-0.0001 Y8.8135 N63 G01 Z9.7163 F500. N64 G98 G84 X-0.0001 Y8.8135 Z6.0376 R7.6376 E10. N65 G98 G84 X-0.0001 Y10.8135 Z6.0376 R7.6376 E10. N66 G80 G01 F500. N67 X-0.0001 Y8.8135 Z9.7163 N68 X-0.0001 Y8.8135 Z9.7163 N69 N70 M845 N71 G91 G28 Z0 N72 G90 N73 M30 %`; // 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