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 = "^(http:\\/\\/|https:\\/\\/)?(www\\.)?[a-zA-Z0-9-_\\.]+\\.[a-zA-Z]+(:\\d+)?(\\/[a-zA-Z\\d\\.\\-_]*)*[a-zA-Z.!@#$%&=-_'\":,.?\\d*)(]*$"; final String string = "http://preview.ynot.com:80/cgibin/nd_CGI-50.cgi/YnotPhoenix/CFsMain\n" + "https://the-parrot-lands.com/ewefwe/fwefwe/jljlk%hkuj\n" + "http://twas.brillig.and.the.slithy.toves.\n" + "http://csrpathway.com\n" + "https://google.com\n" + "https://google.com:8080/\n" + "parrotlands.com/\n" + "http://www.google.com/aa\n" + "http://www.google.com\n" + "https://regex101.info\n" + "http://a.com:8080/asdfas.php?as=3729&asd=df&a=*)fw3287&asdf=223\n" + "101_regix.com/aaa/\n" + "t.me/anhnch\n" + "ig.me/aa/33/22/332833/adasd/eoe/owerw.php\n" + "ww.com/index.php?asd=339298\n" + "http://art.com/artgallery/default.asp?sid=9DF4BC0580DF11D3ACB60090271E26A8&command=freelist\n" + "http://www.drugemporium.com/cec/cstage?eccookie=@eccookie@&ecaction=de_ecwalkin&template=de_walkin.en.htm\n" + "http://www.sfgate.com/cgibin/srch_archive/dropdn_srch.cgi?template=templates2Ftypes2Ffood2Ffd_ddstemplate.shtml&item=templates%2Ftypes%2Ffood%2Ffd_ddsitem.txt&subject=RESTAURANTS%2BAND%2BREVIEW&keyword=shrimp&datesearch=366&year="; 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