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

/
/
gm

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?i)(?<scheme>http|https|ftp|sftp|sip|sips|file):\\/\\/(?:(?<username>[^`!@#$^&*()+=,:;'\"\\{\\}\\|\\[\\]\\s\\/\\\\]+)(?::(?<password>[^`!@#$^&*()+=,:;'\"\\{\\}\\|\\[\\]\\s\\/\\\\]+))?@)?(?:(?<ipv4>((?:(?:25[0-5]|2[0-4]\\d|1?\\d\\d?)\\.){3}(?:25[0-5]|2[0-4]\\d|1?\\d\\d?)))|\\[(?<ipv6>(?i)(?:[\\da-f]{0,4}:){1,7}(?:(?<ipv4_in_ipv6>(?:(?:25[0-5]|2[0-4]\\d|1?\\d\\d?)\\.){3}(?:25[0-5]|2[0-4]\\d|1?\\d\\d?))|[\\da-f]{0,4}))\\]|(?:(?<sub_domain>[^\\s~`!@#$%^&*()_+=,.?:;'\"\\{\\}\\|\\[\\]\\/\\\\]+\\.)*(?<domain>[^\\s~`!@#$%^&*()_+=,.?:;'\"\\{\\}\\|\\[\\]\\/\\\\]+)(?<tld>\\.[^\\s~`!@#$%^&*()\\-_+=,.?:;'\"\\{\\}\\|\\[\\]\\/\\\\0-9]{2,})))+(?<port>:\\d+)?(?:\\/(?<path>\\/?[^\\s`@#$^&=.?\"\\{\\}\\\\]+\\/)*(?<file>[^\\s`@#$^&=?\"\\{\\}\\/\\\\]+)?(?<query>\\?[^\\s`#$^\"\\{\\}\\\\]+)*(?<fragment>#[^\\s`$^&=?\"\\{\\}\\/\\\\]+)?)?"; final String string = "# Quick Example (full)\n" + "https://uSer:pass@sub1.sub-2.EXamPle.uk.com:80/PATH1/paTh2?qUeRy=1&q2=2#ancHor\n" + "https://úser@suß.öctúvt.tìd/file-path/FILE_%82%8A.php?query=value&query2=value2#somethig\n" + "HTTP://دامنه.ایران/زیردامنه/زیردامنه۲/فایل.پسوند؟درخواست=جواب\n" + "http://blog.sergeys.us/beer?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed:+SergeySus+(Sergey+Sus+Photography+%C2%BB+Blog)&utm_content=Google+Reader\n" + "http://test.site/wp-admin/post.php?t=1347548645469?t=1347548651124?t=1347548656685?t=1347548662469?t=1347548672300?t=1347548681615?#sdfsdf\n" + "http://example.com/wp-admin/load-scripts.php?c=1&load[]=swfobject,jquery,utils&ver=3.5\n" + "http://video.google.co.uk:80/videoplay?docid=-7246927612831078230&hl=en#hello\n" + "https://example.com/path/resource.txt#fragment\n\n\n" + "# Basic\n" + "www.example.com\n" + "http://example.com\n" + "https://example.com\n" + "https://example.ac.eu\n" + "https://example.gov.ir\n" + "ftp://example.com\n" + "sftp://example.com\n\n" + "# With Path\n" + "www.example.com/path1/path2/\n" + "http://example.com/path1/path2/\n" + "https://example.com/path1/path2\n\n" + "# With Path & File\n" + "www.example.com/path1/path2/file.pdf\n" + "http://example.com/path1/path2/file.c\n" + "https://example.com/path1/path2/file.txt\n\n" + "# With Path & Query\n" + "http://www.example.com/?query=some-path/path1/path2/\n" + "http://example.com/path1/path2/?query=something\n" + "https://example.com/path1/path2?query=something\n\n" + "# With Subdomain\n" + "sub1.sub2.example.com\n" + "www.example.com\n" + "http://www.example.com\n" + "ftp://sub1.example.com\n\n" + "# With Port\n" + "www.example.com:80\n" + "http://example.com:8080\n" + "ftp://example.com:21\n" + "ftp://sub1.example.com:21\n" + "http://example.com:8080/path1/path2/\n" + "http://example.com:80/path1/path2/file.c\n" + "http://example.com:443/path1/path2/?query=something\n\n" + "# With Username\n" + "user@example.com\n" + "http://user@www.example.com\n" + "ftp://user@example.com\n" + "ftp://user@sub1.example.com:21\n" + "http://user@example.com:8080/path1/path2/\n" + "http://user@example.com/path1/path2/file.c\n" + "http://user@example.com/path1/path2/?query=something\n\n" + "# Some Crazy Examples\n" + "http://ヒキワリ.ナットウ.ニホン\n" + "sip://ßàÁâãóôþüúðæåïçèõöÿýòäœêëìíøù.îûñé\n" + "HTTP://دامنه.ایران/زیردامنه/زیردامنه۲/فایل.پسوند؟درخواست=جواب\n" + "http://example.com/wp-admin/load-scripts.php?c=1&load[]=swfobject,jquery,utils&ver=3.5\n" + "https://úser@sub1.suß2.sub3.öctúvt.tìd.tìd/V3/file-path/P----29BSx_A_%82%8A_D_M1n_a.php?query=value#somethig\n" + "http://www.go.com.au/ersdfs?dfd=dfgd@s=1\n" + "https://uSer@EXamPle.uk.com:80/?qyery?qUeRy=1&q2=2#ancHor\n" + "http://example.com/%E5%BC%95%E3%81%8D%E5%89%B2%E3%82%8A.html\n" + "hTTp://eXamPLE.CoM\n" + "https://belgië.be\n" + "https://belgië.be.gov\n" + "http://user@[2001:db8::1]/\n" + "https://user@111.222.33.44:49171/Cda-cgi/clientcgi?action=start\n" + "http://[2001:db8::1]:80\n" + "a2d.dd4d.d5d.www.go.com.au\n" + "a.b.c.d.e.go.com.co.uk\n" + "go.com.uk\n" + "go.go.com\n" + "1go-co.com\n" + "1-2-3-4--5-go.com\n" + "www.go.com.au\n\n" + "# These Should not be Seen as Domain\n" + "example.c\n" + "example..com\n" + "123.b\n" + "go.12\n" + "1.2.3.4\n" + "ff:ff:ff:ff\n" + "C:\\Program Files (x86)\\Microsoft\\Edge\\Application\\msedge.exe\n" + "hTTps://111.222.533.44:49171/cda-cgi/clientcgi?action=start\n\n\n" + "# These Should be Seen Partially\n" + "//example.com.c\n" + "example.com.c\n" + "http://example.com.com.\n\n" + "# It Should Find URLs in a Text too\n" + "create Share Links to send your expressions to co-workers or link to them on Twitter or your blog [ex. http://RegExr.com?2rjl655] \n" + "Built by gskinner.com with Flex 3 [adobe.com/go/flex] and Spelling Plus Library for text highlighting[gskinner.com/products/spl].\n\n\n" + "# Resources\n" + "- https://en.wikipedia.org/wiki/Uniform_Resource_Identifie\n" + "- https://en.wikipedia.org/wiki/List_of_URI_schemes\n" + "- \n" + "- https://zencoder.support.brightcove.com/general-information/special-characters-usernames-and-passwords.html\n" + "- https://support.microsoft.com/en-us/topic/certain-special-characters-are-not-allowed-in-the-url-entered-into-the-address-bar-of-internet-explorer-a8e2a966-19d6-27af-06cc-e720f25e8b02\n" + "- https://perishablepress.com/stop-using-unsafe-characters-in-urls/\n" + "- https://help.dragonmetrics.com/en/articles/213986-invalid-characters-in-url"; 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