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 = "([\\w+]+\\:\\/\\/)?([\\w\\d-]+\\.)*[\\w-]+[\\(\\)\\#\\.\\:]\\w+([\\(\\)\\/\\?\\=\\&\\#\\.]?[\\w-]+)*\\/?[\\(\\-\\w\\)\\?\\=\\#_]*"; final String string = "https://daringfireball.net/2010/07/improved_regex_for_matching_urls\n" + "Some of the advantages of the new pattern, compared to the previous one:\n" + " It no longer uses the [:punct:] named character class. I thought this was universally supported in modern regex engines, but apparently it is not.\n" + " It does a better job with URLs containing literal parentheses, correctly matching the following URLs that the previous pattern did not:\n" + " .http://foo.com/more_(than)_one_(parens)\n" + " http://foo.com/blah_(wikipedia)#cite-1.\n" + " http://foo.com/blah_(wikipedia)_blah#cite-1.\n" + " http://foo.com/unicode_(✪)_in_parens,\n" + " http://foo.com/(something)?after=parens.\n" + " It now matches mailto: URLs.\n\n" + " It correctly guesses that things like “bit.ly/foo” and “is.gd/foo/” are URLs. Basically: something-dot-something-slash-something.\n" + "teste www.google.com teste\n\n" + "https://www.facebook.com.\n" + "https://app-1.number123.com.\n" + "http://facebook.com.\n" + "ftp://facebook.com\n" + "http://localhost:3000\n" + "localhost:3000/\n" + "unitedkingdomurl.co.uk\n" + "this.is.a.url.com/its/still=going?wow\n" + "shop.facebook.org\n" + "app.number123.com\n" + "app1.number123.com\n" + "app-1.numbEr123.com\n" + "app.dashes-dash.com\n" + "www.facebook.com\n" + "facebook.com\n" + "fb.com/hello_123\n" + "fb.com/hel-lo\n" + "fb.com/hello/goodbye\n" + "fb.com/hello/goodbye?okay\n" + "fb.com/hello/goodbye?okay=alright\n" + "Hello www.google.com World http://yahoo.com\n" + "https://www.google.com.tr/admin/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n" + "https://google.com.tr/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n" + "http://google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n" + "ftp://google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n" + "www.google.com.tr/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n" + "www.google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n" + "drive.google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n" + "https://www.example.pl\n" + "http://www.example.com\n" + "www.example.pl\n" + "example.com\n" + "http://blog.example.com\n" + "http://www.example.com/product\n" + "http://www.example.com/products?id=1&page=2\n" + "http://www.example.com#up\n" + "http://255.255.255.255\n" + "255.255.255.255\n" + "shop.facebook.org/derf.html\n\n" + "Hello www.google.com World http://yahoo.com\n\n" + "https://www.google.com.tr/admin/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n\n" + "https://google.com.tr/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n\n" + "http://google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n\n" + "ftp://google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n\n" + "www.google.com.tr/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n\n" + "www.google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n\n" + "drive.google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services\n\n" + "Will match the following cases\n\n" + " http://www.foufos.gr\n" + " https://www.foufos.gr\n" + " http://foufos.gr\n" + " http://www.foufos.gr/kino\n" + " http://werer.gr\n" + " www.foufos.gr\n" + " www.mp3.com\n" + " www.t.co\n" + " http://t.co\n" + " http://www.t.co\n" + " https://www.t.co\n" + " www.aa.com\n" + " http://aa.com\n" + " http://www.aa.com\n" + " https://www.aa.com\n\n" + "Will NOT match the following\n\n" + " www.foufos\n" + " www.foufos-.gr\n" + " www.-foufos.gr\n" + " foufos.gr\n" + " http://www.foufos\n" + " http://foufos\n" + " www.mp3#.com\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