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 = /1-0:16\.7\.0\*255":(-?\d+\.?\d+)|1-0:2\.8\.0\*255\":(-?\d+\.?\d+)|1-0:1\.8\.0\*255\":(-?\d+\.?\d+)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('1-0:16\\.7\\.0\\*255":(-?\\d+\\.?\\d+)|1-0:2\\.8\\.0\\*255\\":(-?\\d+\\.?\\d+)|1-0:1\\.8\\.0\\*255\\":(-?\\d+\\.?\\d+)', 'gm') const str = `{"meterId":"1KFM0000028196","deviceId":"EBSD1425009486","msgType":"EMETER_OBIS_V2","measurements":[{"timestamp":"2023-04-02T11:32:33Z","values":{"1-0:96.90.2*1":"7E2005D2","1-0:0.2.0*0":"312E3033","1-0:14.7.0*255":49.900001525878906,"1-0:81.7.26*255":52,"1-0:81.7.15*255":331,"1-0:81.7.4*255":188,"1-0:81.7.2*255":239,"1-0:81.7.1*255":117,"1-0:71.7.0*255":1.1100000143051147,"1-0:51.7.0*255":0.73000001907348633,"1-0:31.7.0*255":1.8999999761581421,"1-0:72.7.0*255":235.5,"1-0:52.7.0*255":233.80000305175781,"1-0:32.7.0*255":235.89999389648438,"1-0:16.7.0*255":-152,"1-0:2.8.0*255":0.52590000629425049,"1-0:1.8.0*255":10474.70703125,"1-0:96.1.0*255":"0A014B464D0000006E24","1-0:96.50.1*1":"4B464D"}}]}`; // 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