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

/
/
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 = "<meta (?:name|http-equiv)='(.*)' content='(.*)'>"; final String string = "<meta charset='UTF-8'>\n" + "<meta name='keywords' content='your, tags'>\n" + "<meta name='description' content='150 words'>\n" + "<meta name='subject' content='your website's subject'>\n" + "<meta name='copyright' content='company name'>\n" + "<meta name='language' content='ES'>\n" + "<meta name='robots' content='index,follow'>\n" + "<meta name='revised' content='Sunday, July 18th, 2010, 5:15 pm'>\n" + "<meta name='abstract' content=''>\n" + "<meta name='topic' content=''>\n" + "<meta name='summary' content=''>\n" + "<meta name='Classification' content='Business'>\n" + "<meta name='author' content='name, email@hotmail.com'>\n" + "<meta name='designer' content=''>\n" + "<meta name='reply-to' content='email@hotmail.com'>\n" + "<meta name='owner' content=''>\n" + "<meta name='url' content='http://www.websiteaddrress.com'>\n" + "<meta name='identifier-URL' content='http://www.websiteaddress.com'>\n" + "<meta name='directory' content='submission'>\n" + "<meta name='pagename' content='jQuery Tools, Tutorials and Resources - O'Reilly Media'>\n" + "<meta name='category' content=''>\n" + "<meta name='coverage' content='Worldwide'>\n" + "<meta name='distribution' content='Global'>\n" + "<meta name='rating' content='General'>\n" + "<meta name='revisit-after' content='7 days'>\n" + "<meta name='subtitle' content='This is my subtitle'>\n" + "<meta name='target' content='all'>\n" + "<meta name='HandheldFriendly' content='True'>\n" + "<meta name='MobileOptimized' content='320'>\n" + "<meta name='date' content='Sep. 27, 2010'>\n" + "<meta name='search_date' content='2010-09-27'>\n" + "<meta name='DC.title' content='Unstoppable Robot Ninja'>\n" + "<meta name='ResourceLoaderDynamicStyles' content=''>\n" + "<meta name='medium' content='blog'>\n" + "<meta name='syndication-source' content='https://mashable.com/2008/12/24/free-brand-monitoring-tools/'>\n" + "<meta name='original-source' content='https://mashable.com/2008/12/24/free-brand-monitoring-tools/'>\n" + "<meta name='verify-v1' content='dV1r/ZJJdDEI++fKJ6iDEl6o+TMNtSu0kv18ONeqM0I='>\n" + "<meta name='y_key' content='1e39c508e0d87750'>\n" + "<meta name='pageKey' content='guest-home'>\n" + "<meta itemprop='name' content='jQTouch'>\n" + "<meta http-equiv='Expires' content='0'>\n" + "<meta http-equiv='Pragma' content='no-cache'>\n" + "<meta http-equiv='Cache-Control' content='no-cache'>\n" + "<meta http-equiv='imagetoolbar' content='no'>\n" + "<meta http-equiv='x-dns-prefetch-control' content='off'>"; 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