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

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 = "( [0-9]{2,3}.[0-9]{1} .[0-9]{2,3}.[0-9]{1} )"; final String string = "Start: 2020-02-01T10:08:41-0500\n" + "HOST: detectgooglesp.com Loss% Snt Last Avg Best Wrst StDev\n" + " 1.|-- 148.163.220.1 0.0% 15 6.3 9.1 2.9 32.7 7.8\n" + " 2.|-- 148.163.219.28 0.0% 15 3.1 7.0 2.3 22.4 5.0\n" + " 3.|-- 187.16.216.55 0.0% 15 5.5 6.6 2.9 16.6 3.3\n" + " 4.|-- 74.125.243.12 0.0% 15 7.4 6.1 3.6 10.6 1.9\n" + " 5.|-- 209.85.252.68 0.0% 15 18.2 16.7 3.6 14.1 3.0\n" + " 6.|-- 66.249.94.109 0.0% 15 108.3 110.1 106.7 120.9 4.1\n" + " 7.|-- 74.125.251.34 0.0% 15 120.9 122.9 120.2 130.5 3.0\n" + " 8.|-- 216.239.40.141 0.0% 15 131.0 129.6 128.1 132.3 1.1\n" + " 9.|-- 209.85.250.206 0.0% 15 141.0 145.7 141.0 162.7 5.8\n" + " 10.|-- 209.85.253.209 0.0% 15 154.8 144.7 140.6 155.0 4.4\n" + " 11.|-- 209.85.244.207 0.0% 15 141.9 152.6 141.9 229.7 22.7\n" + " 12.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 13.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 14.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 15.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 16.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 17.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 18.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 19.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 20.|-- ??? 100.0 15 0.0 0.0 0.0 0.0 0.0\n" + " 21.|-- 35.226.130.1 0.0% 15 144.5 143.1 141.1 151.6 2.6\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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