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

/
/
g

Test String

Code Generator

Language

Generated Code

const regex = /\[(?P<timestamp>[\w-]+\s[\w:]+[+\.]\d+)\] \[(?P<level>\S+)\]\:(?P<bho>\s+)\t\{(?P<id>\d+)\} \[(?P<telefono>\S+)\] \[(?P<ip>\S+)\] (?P<node>\w*)\s*\[(?P<path>\S+)?\s\]\[(?P<bho2>\s\d+\s)\]\[\s(?P<id2>\d+\s)\]/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('\\[(?P<timestamp>[\\w-]+\\s[\\w:]+[+\\.]\\d+)\\] \\[(?P<level>\\S+)\\]\\:(?P<bho>\\s+)\\t\\{(?P<id>\\d+)\\} \\[(?P<telefono>\\S+)\\] \\[(?P<ip>\\S+)\\] (?P<node>\\w*)\\s*\\[(?P<path>\\S+)?\\s\\]\\[(?P<bho2>\\s\\d+\\s)\\]\\[\\s(?P<id2>\\d+\\s)\\]', 'g') const str = `[2020-05-22 12:49:09.1640] [info]: {2012} [393471039213] [10.8.19.191] MASTER [netmon.condiviso_368-pwc ][ 160239552803493 ][ 1292 ] [2020-02-13 01:01:03.9170] [info]: {2} [393454639076] [10.8.4.218] MASTER [netmon.condiviso_368-pwc ][ 160130554375066 ][ 1855 ] [2020-02-13 02:10:05.5750] [info]: {499} [393481505158] [10.8.17.5] [netmon.traffico.393481505158.10.8.17.5_371-pwc ][ 4880942571 ][ 16274 ]`; // 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