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

r"
"
gmi

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('(?<=[\\s\\b()-])(\\d+)(\\.\\d+)?(?=\\s?[A-Za-z]?)((\\s?[kmgtpun])?(i?b/?s?|s|hz)?)(?=[]\\s\\b()[]|$)', 'gmi') const str = ` 70 02 [95386.467810]= 50 MiB 28414 (1806 ms in 2 ms) in 5 ms 2.74GHz 434MHz 90kHz 23Hz 1.7k 2 ul 07 [2484867] 41666 KiB/s 29107 [17755556] 0s [ | 2.74 GHz 434 MHz 90 KHz 45 kHz 23 Hz [143M 8317 (-70831 us) 10023ms ()-> 10022ms ( (37.9 kHz e) 0.389978] pci 4ns 1.4M 9986 [100k Sep-22] 468G 163G 282G 3 511M 5.3M 506M 5.5T 4.3T 1.3T 1.2T 890M 236G -l 1.1T 17G ) 3.4T c 1.1T 1.7T cinema 15G software 446G software 5.5T total 29k x 4 4.1k 23-Sr 4.1k 2 r 4.1k 1 4.1k :38 5 ter 4.1k r 4.1k st 23-Feb "2022-09-21T00:49:08.191147376+03:00"p4* 2% /boot/efi @ 192.168.1.2 :/mnt/6Sep (0) g 02:45:46 done 600 601 605 628 +h 00:48:22  0312./05 III (2020-2021) 1`; // 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