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

/
/
gmi

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 = "^(?:(?:ds|crl|ocsp|dnl\\-[0,1][0-9]\\.geo|(?:[sp][0,1][0-9]|downloads)\\.upd)\\.kaspersky|downloads[0-9]?\\.kaspersky\\-labs)\\.com$"; final String string = "ds.kaspersky.com\n" + "dnl-01.geo.kaspersky.com\n" + "dnl-02.geo.kaspersky.com\n" + "dnl-03.geo.kaspersky.com\n" + "dnl-04.geo.kaspersky.com\n" + "dnl-05.geo.kaspersky.com\n" + "dnl-06.geo.kaspersky.com\n" + "dnl-07.geo.kaspersky.com\n" + "dnl-08.geo.kaspersky.com\n" + "dnl-09.geo.kaspersky.com\n" + "dnl-10.geo.kaspersky.com\n" + "dnl-11.geo.kaspersky.com\n" + "dnl-12.geo.kaspersky.com\n" + "dnl-13.geo.kaspersky.com\n" + "dnl-14.geo.kaspersky.com\n" + "dnl-15.geo.kaspersky.com\n" + "dnl-16.geo.kaspersky.com\n" + "dnl-17.geo.kaspersky.com\n" + "dnl-18.geo.kaspersky.com\n" + "dnl-19.geo.kaspersky.com\n" + "dnl-00.geo.kaspersky.com\n" + "s00.upd.kaspersky.com\n" + "s01.upd.kaspersky.com\n" + "s02.upd.kaspersky.com\n" + "s03.upd.kaspersky.com\n" + "s04.upd.kaspersky.com\n" + "s05.upd.kaspersky.com\n" + "s06.upd.kaspersky.com\n" + "s07.upd.kaspersky.com\n" + "s08.upd.kaspersky.com\n" + "s09.upd.kaspersky.com\n" + "s10.upd.kaspersky.com\n" + "s11.upd.kaspersky.com\n" + "s12.upd.kaspersky.com\n" + "s13.upd.kaspersky.com\n" + "s14.upd.kaspersky.com\n" + "s15.upd.kaspersky.com\n" + "s16.upd.kaspersky.com\n" + "s17.upd.kaspersky.com\n" + "s18.upd.kaspersky.com\n" + "s19.upd.kaspersky.com\n" + "p00.upd.kaspersky.com\n" + "p01.upd.kaspersky.com\n" + "p02.upd.kaspersky.com\n" + "p03.upd.kaspersky.com\n" + "p04.upd.kaspersky.com\n" + "p05.upd.kaspersky.com\n" + "p06.upd.kaspersky.com\n" + "p07.upd.kaspersky.com\n" + "p08.upd.kaspersky.com\n" + "p09.upd.kaspersky.com\n" + "p10.upd.kaspersky.com\n" + "p11.upd.kaspersky.com\n" + "p12.upd.kaspersky.com\n" + "p13.upd.kaspersky.com\n" + "p14.upd.kaspersky.com\n" + "p15.upd.kaspersky.com\n" + "p16.upd.kaspersky.com\n" + "p17.upd.kaspersky.com\n" + "p18.upd.kaspersky.com\n" + "p19.upd.kaspersky.com\n" + "downloads.upd.kaspersky.com\n" + "crl.kaspersky.com\n" + "ocsp.kaspersky.com\n" + "downloads.kaspersky-labs.com\n" + "downloads0.kaspersky-labs.com\n" + "downloads1.kaspersky-labs.com\n" + "downloads2.kaspersky-labs.com\n" + "downloads3.kaspersky-labs.com\n" + "downloads4.kaspersky-labs.com\n" + "downloads5.kaspersky-labs.com\n" + "downloads6.kaspersky-labs.com\n" + "downloads7.kaspersky-labs.com\n" + "downloads8.kaspersky-labs.com\n" + "downloads9.kaspersky-labs.com\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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