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"
"
g

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 = "HTTP\\/\\d\\.\\d\\s(\\d{3})"; final String string = "HTTP/1.1 302 See other\n" + "Date: Tue, 17 Feb 2015 20:20:48 GMT\n" + "Server: Apache\n" + "X-Powered-By: PHP/5.5.21\n" + "Set-Cookie: 5e8627afafd16a920dac4dbb644715a5=ue1gprimq6rb5r4qsb8sk28jb2; path=/; HttpOnly\n" + "Location: http://fake.dk/da/\n" + "Connection: close\n" + "Content-Type: text/html; charset=utf-8\n" + "Set-Cookie: SERVERID=; path=/\n\n" + "HTTP/1.1 200 OK\n" + "Date: Tue, 17 Feb 2015 20:20:48 GMT\n" + "Server: Apache\n" + "X-Powered-By: PHP/5.5.21\n" + "Set-Cookie: 76726d50abd3edd601ecfbc19fe61c87=da-DK; path=/\n" + "Set-Cookie: 76726d50abd3edd601ecfbc19fe61c87=da-DK\n" + "P3P: CP=\"NOI ADM DEV PSAi COM NAV OUR OTRo STP IND DEM\"\n" + "Expires: Mon, 1 Jan 2001 00:00:00 GMT\n" + "Last-Modified: Tue, 17 Feb 2015 20:20:48 GMT\n" + "Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0\n" + "Pragma: no-cache\n" + "Connection: close\n" + "Content-Type: text/html; charset=utf-8\n" + "Set-Cookie: SERVERID=; path=/\n\n" + "<!doctype html>\n\n" + "<html lang=\"da\">\n" + "<head>\n" + "</head>\n\n" + "<body>\n" + "</body>\n" + "</html>"; final Pattern pattern = Pattern.compile(regex); 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