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

Substitution

Processing...

Code Generator

Language

Generated Code

re = /^.*Download:\s{3,5}\K\d{1,3}\.\d{0,2}(?= Mbps)/m str = ' Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 29.13 ms (jitter: 7.59ms, low: 22.73ms, high: 33.85ms) Download: 238.14 Mbps (data used: 384.0 MB) 603.92 ms (jitter: 87.34ms, low: 37.24ms, high: 1203.74ms) Upload: 46.48 Mbps (data used: 43.4 MB) 172.46 ms (jitter: 54.67ms, low: 37.41ms, high: 304.20ms) Packet Loss: 0.0% Result URL: https://www.speedtest.net/result/c/f4f1d464-82c6-4980-8b3f-38358ccedbfb Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 23.63 ms (jitter: 0.51ms, low: 23.25ms, high: 25.28ms) Download: 209.23 Mbps (data used: 356.9 MB) 629.97 ms (jitter: 87.98ms, low: 34.60ms, high: 966.30ms) Upload: 44.29 Mbps (data used: 39.4 MB) 179.07 ms (jitter: 54.45ms, low: 55.78ms, high: 288.01ms) Packet Loss: 0.0% Result URL: https://www.speedtest.net/result/c/ab0ea00c-28c1-4ab0-a65e-3e49ec70160f Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 23.36 ms (jitter: 5.38ms, low: 22.38ms, high: 32.22ms) Download: 190.75 Mbps (data used: 341.4 MB) 811.89 ms (jitter: 81.96ms, low: 38.70ms, high: 1557.16ms) Upload: 46.68 Mbps (data used: 78.4 MB) 177.39 ms (jitter: 57.87ms, low: 54.85ms, high: 636.20ms) Packet Loss: 0.0% Result URL: https://www.speedtest.net/result/c/6618ad7c-8990-4e8c-9ccf-b2d8726e5757 Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 23.37 ms (jitter: 0.97ms, low: 22.43ms, high: 24.39ms) Download: 7.30 Mbps (data used: 9.5 MB) 788.00 ms (jitter: 148.57ms, low: 195.04ms, high: 2617.58ms) Download: FAILED Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 24.34 ms (jitter: 5.23ms, low: 23.35ms, high: 32.27ms) Download: 29.70 Mbps (data used: 36.9 MB) 2842.76 ms (jitter: 102.51ms, low: 36.73ms, high: 3780.32ms) Upload: 7.91 Mbps (data used: 11.4 MB) 642.92 ms (jitter: 85.25ms, low: 168.67ms, high: 1465.30ms) Packet Loss: 0.0% Result URL: https://www.speedtest.net/result/c/c625078c-1efb-4d0c-86f6-47f85ee1838e Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 23.40 ms (jitter: 0.75ms, low: 22.38ms, high: 24.37ms) Download: 48.79 Mbps (data used: 53.9 MB) 1605.18 ms (jitter: 98.93ms, low: 51.83ms, high: 2609.00ms) Upload: 10.45 Mbps (data used: 5.4 MB) 350.75 ms (jitter: 80.15ms, low: 60.41ms, high: 742.65ms) Packet Loss: 0.0% Result URL: https://www.speedtest.net/result/c/594b8f34-673c-4670-a091-56104e909153 Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 24.63 ms (jitter: 4.15ms, low: 24.34ms, high: 32.18ms) Download: 58.12 Mbps (data used: 69.5 MB) 1889.25 ms (jitter: 101.87ms, low: 96.60ms, high: 3067.85ms) Upload: 10.45 Mbps (data used: 18.9 MB) 591.63 ms (jitter: 88.04ms, low: 79.24ms, high: 1231.14ms) Packet Loss: 0.0% Result URL: https://www.speedtest.net/result/c/35fd9653-3907-4ddd-8680-8ca69b2f0de7 Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 22.87 ms (jitter: 1.21ms, low: 22.35ms, high: 23.94ms) Download: 65.27 Mbps (data used: 76.1 MB) 1603.47 ms (jitter: 97.63ms, low: 48.89ms, high: 2508.82ms) Upload: 10.92 Mbps (data used: 8.3 MB) 403.47 ms (jitter: 83.73ms, low: 77.31ms, high: 814.42ms) Packet Loss: 0.0% Result URL: https://www.speedtest.net/result/c/8de80c8e-cf49-43ee-8964-133e25c7e783 Speedtest by Ookla Server: Fastweb SpA - Milan (id: 7839) ISP: Wind Tre Idle Latency: 24.64 ms (jitter: 1.16ms, low: 22.85ms, high: 25.41ms) Download: 66.83 Mbps (data used: 77.7 MB) ' subst = '' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html