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 = /(Send: (N\d+\s+)?(G0|G1|G2|G3)).*|(Recv: ok)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(Send: (N\\d+\\s+)?(G0|G1|G2|G3)).*|(Recv: ok)', 'gm') const str = `Send: N15316 G2 X132.005 Y144.699 I2.530 J2.266 E1967.48230*80 Recv: ok Send: N15317 G2 X130.872 Y146.440 I8.090 J6.504 E1967.55146*83 Recv: ok Send: N15318 G3 X128.033 Y150.765 I-83.048 J-51.420 E1967.72359*80 Recv: ok Send: N15319 G2 X126.450 Y152.896 I19.401 J16.065 E1967.81191*88 Recv: ok Send: N15320 G3 X123.581 Y158.450 I-52.577 J-23.641 E1968.01996*86 Recv: ok Send: N3830 G1 F1800 X137.124 Y134.295 E1247.73559*2 Recv: ok Send: N3831 G0 F7200 X137.525 Y134.131*112 Recv: ok Send: N3832 G1 F1800 X173.8 Y170.406 E1249.44186*15 Recv: ok Send: N3833 G0 F7200 X173.957 Y169.997*119 Recv: == T:209.96 /210.00 == B:60.21 /60.00 @:79 B@:127 Recv: ok Send: N3834 G1 F1800 X137.95 Y133.991 E1251.13549*53 Recv: ok Send: N3835 G0 F7200 X138.404 Y133.878*122 Recv: ok Send: N3836 G1 F1800 X174.132 Y169.606 E1252.81603*7 Recv: ok Send: N3837 G0 F7200 X174.242 Y169.151*121 Recv: == T:209.73 /210.00 == B:60.66 /60.00 @:85 B@:0 Recv: ok Send: N3838 G1 F1800 X138.857 Y133.766 E1254.48043*2 Recv: ok Send: N3839 G0 F7200 X139.311 Y133.654*116 Recv: == T:209.77 /210.00 == B:60.69 /60.00 @:84 B@:0 Recv: ok Send: N3840 G1 F1800 X174.354 Y168.697 E1256.12874*13 Recv: ok Send: N3841 G0 F7200 X174.465 Y168.242*123 Recv: ok Send: N3842 G1 F1800 X139.775 Y133.553 E1257.76043*11 Recv: ok Send: N3843 G0 F7200 X140.258 Y133.469*119 Recv: == T:209.92 /210.00 == B:60.65 /60.00 @:79 B@:0 Recv: ok `; // 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