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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^.*Download:\\s{3,5}\\K\\d{1,3}\\.\\d{0,2}(?= Mbps)"; final String string = " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 29.13 ms (jitter: 7.59ms, low: 22.73ms, high: 33.85ms)\n" + " Download: 238.14 Mbps (data used: 384.0 MB)\n" + " 603.92 ms (jitter: 87.34ms, low: 37.24ms, high: 1203.74ms)\n" + " Upload: 46.48 Mbps (data used: 43.4 MB)\n" + " 172.46 ms (jitter: 54.67ms, low: 37.41ms, high: 304.20ms)\n" + " Packet Loss: 0.0%\n" + " Result URL: https://www.speedtest.net/result/c/f4f1d464-82c6-4980-8b3f-38358ccedbfb\n\n" + " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 23.63 ms (jitter: 0.51ms, low: 23.25ms, high: 25.28ms)\n" + " Download: 209.23 Mbps (data used: 356.9 MB)\n" + " 629.97 ms (jitter: 87.98ms, low: 34.60ms, high: 966.30ms)\n" + " Upload: 44.29 Mbps (data used: 39.4 MB)\n" + " 179.07 ms (jitter: 54.45ms, low: 55.78ms, high: 288.01ms)\n" + " Packet Loss: 0.0%\n" + " Result URL: https://www.speedtest.net/result/c/ab0ea00c-28c1-4ab0-a65e-3e49ec70160f\n\n" + " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 23.36 ms (jitter: 5.38ms, low: 22.38ms, high: 32.22ms)\n" + " Download: 190.75 Mbps (data used: 341.4 MB)\n" + " 811.89 ms (jitter: 81.96ms, low: 38.70ms, high: 1557.16ms)\n" + " Upload: 46.68 Mbps (data used: 78.4 MB)\n" + " 177.39 ms (jitter: 57.87ms, low: 54.85ms, high: 636.20ms)\n" + " Packet Loss: 0.0%\n" + " Result URL: https://www.speedtest.net/result/c/6618ad7c-8990-4e8c-9ccf-b2d8726e5757\n\n" + " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 23.37 ms (jitter: 0.97ms, low: 22.43ms, high: 24.39ms)\n" + " Download: 7.30 Mbps (data used: 9.5 MB)\n" + " 788.00 ms (jitter: 148.57ms, low: 195.04ms, high: 2617.58ms)\n" + " Download: FAILED\n\n" + " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 24.34 ms (jitter: 5.23ms, low: 23.35ms, high: 32.27ms)\n" + " Download: 29.70 Mbps (data used: 36.9 MB)\n" + " 2842.76 ms (jitter: 102.51ms, low: 36.73ms, high: 3780.32ms)\n" + " Upload: 7.91 Mbps (data used: 11.4 MB)\n" + " 642.92 ms (jitter: 85.25ms, low: 168.67ms, high: 1465.30ms)\n" + " Packet Loss: 0.0%\n" + " Result URL: https://www.speedtest.net/result/c/c625078c-1efb-4d0c-86f6-47f85ee1838e\n\n" + " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 23.40 ms (jitter: 0.75ms, low: 22.38ms, high: 24.37ms)\n" + " Download: 48.79 Mbps (data used: 53.9 MB)\n" + " 1605.18 ms (jitter: 98.93ms, low: 51.83ms, high: 2609.00ms)\n" + " Upload: 10.45 Mbps (data used: 5.4 MB)\n" + " 350.75 ms (jitter: 80.15ms, low: 60.41ms, high: 742.65ms)\n" + " Packet Loss: 0.0%\n" + " Result URL: https://www.speedtest.net/result/c/594b8f34-673c-4670-a091-56104e909153\n\n" + " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 24.63 ms (jitter: 4.15ms, low: 24.34ms, high: 32.18ms)\n" + " Download: 58.12 Mbps (data used: 69.5 MB)\n" + " 1889.25 ms (jitter: 101.87ms, low: 96.60ms, high: 3067.85ms)\n" + " Upload: 10.45 Mbps (data used: 18.9 MB)\n" + " 591.63 ms (jitter: 88.04ms, low: 79.24ms, high: 1231.14ms)\n" + " Packet Loss: 0.0%\n" + " Result URL: https://www.speedtest.net/result/c/35fd9653-3907-4ddd-8680-8ca69b2f0de7\n\n" + " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 22.87 ms (jitter: 1.21ms, low: 22.35ms, high: 23.94ms)\n" + " Download: 65.27 Mbps (data used: 76.1 MB)\n" + " 1603.47 ms (jitter: 97.63ms, low: 48.89ms, high: 2508.82ms)\n" + " Upload: 10.92 Mbps (data used: 8.3 MB)\n" + " 403.47 ms (jitter: 83.73ms, low: 77.31ms, high: 814.42ms)\n" + " Packet Loss: 0.0%\n" + " Result URL: https://www.speedtest.net/result/c/8de80c8e-cf49-43ee-8964-133e25c7e783\n\n" + " Speedtest by Ookla\n\n" + " Server: Fastweb SpA - Milan (id: 7839)\n" + " ISP: Wind Tre\n" + "Idle Latency: 24.64 ms (jitter: 1.16ms, low: 22.85ms, high: 25.41ms)\n" + " Download: 66.83 Mbps (data used: 77.7 MB)\n"; final String subst = ""; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + 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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html