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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(?<=[\s\b()-])(\d+)(\.\d+)?(?=\s?[A-Za-z]?)((\s?[kmgtpun])?(i?b/?s?|s|hz)?)(?=[]\s\b()[]|$)" test_str = (" 70 02 [95386.467810]= 50 MiB 28414 (1806 ms in 2 ms) in 5 ms 2.74GHz 434MHz 90kHz 23Hz 1.7k 2\n" "ul 07 [2484867] 41666 KiB/s 29107 [17755556] 0s [ | 2.74 GHz 434 MHz 90 KHz 45 kHz 23 Hz [143M \n" " 8317 (-70831 us) 10023ms ()-> 10022ms ( (37.9 kHz e) 0.389978] pci 4ns 1.4M 9986 [100k Sep-22]\n" " 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\n\n" "23-Feb \"2022-09-21T00:49:08.191147376+03:00\"p4* 2% /boot/efi\n" " @ 192.168.1.2 :/mnt/6Sep (0) g 02:45:46 done 600 601 605 628 +h\n" "00:48:22  0312./05 III (2020-2021) 1") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html