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 = "https:\\/\\/(youtu.be|www.youtube.com)\\/([A-z0-9-_]{11}(\\?.*)?$|(watch?.*v=[A-z0-9-_]{11}(\\&.*)?$))"; final String string = "https://www.youtube.com/watch?v=XNADRNnzP8I\n" + "https://www.youtube.com/watch?v=z4plxUWOHxw&t=1s\n" + "https://youtu.be/UW3pBCArsTg\n" + "https://www.youtube.com/watch?v=4HpjbvLeM3Y&t=124s\n" + "https://youtu.be/7Jub0c-qQGM\n" + "https://www.youtube.com/watch?v=vksABX_yYN0&t=1451s\n" + "https://youtu.be/3dHtbo5wwx4\n" + "https://www.youtube.com/watch?v=7QPhMbs2Bd8&t=41s\n" + "https://www.youtube.com/watch?v=YD2_pXJTcAU\n" + "https://youtu.be/9bDSzO8wtCA\n" + "https://www.youtube.com/watch?v=4xfNhseN25E&t=272s\n" + "https://youtu.be/pKUggMsbQt0?123=asd\n" + "https://www.youtube.com/watch?v=Vfw8dIp2Oek&t=693s\n" + "https://www.youtube.com/watch?v=rGYrDPnMCZI\n" + "https://www.youtube.com/watch?v=Sgy0N8YDYPU&t=13s\n" + "https://www.youtube.com/watch?v=KmhBN8CpCcc&t=53s\n" + "https://www.youtube.com/watch?v=dHhyJTSbCbo\n" + "https://www.youtube.com/watch?v=11pqaRiNyiE&t=325s\n" + "https://youtu.be/tYWTrORF7QA\n" + "https://www.youtube.com/watch?v=PQBA2FWST4s&t=7s\n" + "https://www.youtube.com/watch?v=Av8TwjclvV0&t=1459s\n" + "https://www.youtube.com/watch?v=0N0vtsHlAr8&t=732s\n" + "https://www.youtube.com/watch?v=LbLysiDLDYo&t=2347s\n" + "https://www.youtube.com/watch?v=URuA-IQmvUE&t=111s\n" + "https://www.youtube.com/watch?v=5kdCFpeC8as&t=532s\n" + "https://www.youtube.com/watch?v=a5Ck3EZkzMQ\n" + "https://www.youtube.com/watch?v=Gk0Slcw9IiU&t=78s\n" + "https://www.youtube.com/watch?v=bFIhb5xhQRM&t=155s\n" + "https://www.youtube.com/watch?v=37bRMNI4Nv8&t=260s\n" + "https://www.youtube.com/watch?v=gjC20PWBv8A&t=507s\n" + "https://www.youtube.com/watch?v=mGrUtnIVoTU&t=7s\n" + "https://www.youtube.com/watch?v=Tksj76FEWM0&t=208s\n" + "https://www.youtube.com/watch?v=CM0qCSVqz0U&t=551s\n" + "https://www.youtube.com/watch?v=NUkSxLq-jRY&t=69s\n" + "https://www.youtube.com/watch?v=wARglhlugmw&t=52s\n" + "https://www.youtube.com/watch?v=uVHlgd-ipGc&t=18s\n" + "https://www.youtube.com/watch?v=rq0JVTztvXQ&t=4s\n" + "https://www.youtube.com/watch?v=vmE4jQwkbEs&t=420s\n" + "https://www.youtube.com/watch?v=o_HWltTv950&t=146s\n" + "https://www.youtube.com/watch?v=4oroFDP4pA0&t=1057s\n" + "https://youtu.be/fw_RXOylU4c\n" + "https://www.youtube.com/watch?v=MKg2K3E7azs\n" + "https://www.youtube.com/watch?v=CetfYpRaJ9c&t=221s\n" + "https://youtu.be/lkyz58i25Xs\n" + "https://www.youtube.com/watch?v=W5qkaDDVTOA\n" + "https://www.youtube.com/watch?v=jycn7qwMVEI\n" + "https://www.youtube.com/watch?v=cjxe37XrQpI\n" + "https://youtu.be/MIqi2AgkYt8\n" + "https://www.youtube.com/watch?v=-cMOJyhd3BM&t=404s\n" + "https://www.youtube.com/watch?v=yyU7sm4DlzQ\n" + "https://youtu.be/uSJWi7a4fcs\n" + "https://www.youtube.com/watch?v=8ysrYnbEAQw&t=45s\n" + "https://www.youtube.com/watch?v=NrMoafPlvlg\n" + "https://youtu.be/uJVAkOwKs1I\n" + "https://www.youtube.com/watch?v=MqSO4snfEOk&t=98s\n" + "https://www.youtube.com/watch?v=ekedLxblmS0&t=171s\n" + "https://www.youtube.com/watch?v=dZ-6WmB8qyA\n" + "https://youtu.be/20DaWpQqDjM\n" + "https://www.youtube.com/watch?v=bZuaYnRPa2A\n" + "https://www.youtube.com/watch?v=Eve6nu2JOq0\n" + "https://youtu.be/MpzKeLIoLxk\n" + "https://www.youtube.com/watch?v=EJVGXBNNp8M&t=713s\n" + "https://www.youtube.com/watch?v=e1z08cdAdDg\n" + "https://www.youtube.com/watch?v=k3YTIgyKVOU&t=31s\n" + "https://youtu.be/d1bDvS6aSVQ\n" + "https://www.youtube.com/watch?v=owk62eGMGYk\n" + "https://youtu.be/BLEiCSj5zQ0\n" + "https://www.youtube.com/watch?v=g5XdeHy4LEY\n" + "https://youtu.be/FQ6M2sBmOb0\n" + "https://www.youtube.com/watch?v=IS9uOqtvzek\n" + "https://www.youtube.com/watch?v=YStRsFNgD0o\n" + "https://youtu.be/lCyZLHqBjrQ\n" + "https://www.youtube.com/watch?v=WtL1BO8LCoQ\n" + "https://www.youtube.com/watch?v=T_XTYAULs14\n" + "https://www.youtube.com/watch?v=7IP0KEgNwJU\n" + "https://youtu.be/7_IGRl_FwB8\n" + "https://www.youtube.com/watch?v=lamQWEv1wac\n" + "https://www.youtube.com/watch?v=gi1hJfwCO8Q\n" + "https://www.youtube.com/watch?v=xixi27wgudI\n" + "https://www.youtube.com/watch?v=Uq1NcykRak4\n" + "https://www.youtube.com/watch?v=ujYzPaf2aKc\n" + "https://www.youtube.com/watch?v=8NV7kpH9uDE\n" + "https://www.youtube.com/watch?v=lqvv6zvpMLE\n" + "https://www.youtube.com/watch?v=ZYqOUdkfWnA\n" + "https://www.youtube.com/watch?v=dg5fLcelcDI\n" + "https://www.youtube.com/watch?v=keBU3oaEXBg\n" + "https://www.youtube.com/watch?v=rV4tzby21x4\n" + "https://www.youtube.com/watch?v=tBDtUw0mm3o\n" + "https://www.youtube.com/watch?v=vlew8sTDxaA\n" + "https://www.youtube.com/watch?v=eah-0l3oj14\n" + "https://www.youtube.com/watch?v=vavpy-tkxEs\n" + "https://www.youtube.com/watch?v=htmbpUJb9sQ&t=15s\n" + "https://www.youtube.com/watch?v=MPHKXJdKC7Y&t=50s\n" + "https://www.youtube.com/watch?v=4VyoXAm2-ls&t=99s\n" + "https://www.youtube.com/watch?v=O3KK36CTb6Q&t=38s\n" + "https://www.youtube.com/watch?v=ACQtBkfxAws&t=318s\n" + "https://www.youtube.com/watch?v=_6bf6yFf720&t=79s\n" + "https://www.youtube.com/watch?v=Z8NuE57MhIE\n" + "https://www.youtube.com/watch?v=xAITTZqAwTU\n" + "https://www.youtube.com/watch?v=Bz3yBhuBtyw&t=51s\n" + "https://www.youtube.com/watch?v=J7jnUBCoxVk&t=26s\n" + "https://www.youtube.com/watch?v=DKafoAPOVfE\n" + "https://www.youtube.com/watch?v=_Wdq0MNCsTw\n" + "https://www.youtube.com/watch?v=DMJ7AGow2Ms\n" + "https://www.youtube.com/watch?v=17yMzN4Usp8\n" + "https://www.youtube.com/watch?v=a2eobordR8c\n" + "https://www.youtube.com/watch?v=rkouxiiQWko\n" + "https://www.youtube.com/watch?v=LErNVYSmmlg\n" + "https://www.youtube.com/watch?v=tQhT1fQQfCY\n" + "https://www.youtube.com/watch?v=7blDQn69970\n" + "https://www.youtube.com/watch?v=KeOkY7RaZ8E\n" + "https://www.youtube.com/watch?v=80bEG1-v3Hw\n" + "https://www.youtube.com/watch?v=xf726v3XRZ8\n" + "https://www.youtube.com/watch?v=VRhOgs3fFZk\n" + "https://www.youtube.com/watch?v=4VyoXAm2-ls&t=101s\n" + "https://www.youtube.com/watch?v=O3KK36CTb6Q&t=96s\n" + "https://www.youtube.com/watch?v=N6KMLAftrjk&t=16s\n" + "https://www.youtube.com/watch?v=rYSmIh5X6iY&t=20s\n" + "https://www.youtube.com/watch?v=ACQtBkfxAws&t=332s\n" + "https://www.youtube.com/watch?v=_6bf6yFf720&t=79s\n" + "https://www.youtube.com/watch?v=Z8NuE57MhIE\n" + "https://www.youtube.com/watch?v=xAITTZqAwTU\n" + "https://www.youtube.com/watch?v=Bz3yBhuBtyw&t=51s\n" + "https://www.youtube.com/watch?v=J7jnUBCoxVk&t=26s\n" + "https://www.youtube.com/watch?v=SWRasNLVfck\n" + "https://www.youtube.com/watch?v=DKafoAPOVfE\n" + "https://www.youtube.com/watch?v=-cMOJyhd3BM&t=404s\n" + "https://www.youtube.com/watch?v=yyU7sm4DlzQ\n" + "https://www.youtube.com/watch?v=_Wdq0MNCsTw\n" + "https://www.youtube.com/watch?v=lh_FKA1c5TM\n" + "https://www.youtube.com/watch?v=DMJ7AGow2Ms\n" + "https://www.youtube.com/watch?v=17yMzN4Usp8\n" + "https://www.youtube.com/watch?v=TKSU40dCVwQ\n" + "https://www.youtube.com/watch?v=eMAXGmhFupo&t=1s\n" + "https://youtu.be/MpzKeLIoLxk\n" + "https://www.youtube.com/watch?v=EJVGXBNNp8M&t=713s\n" + "https://www.youtube.com/watch?v=pPq6IkJme0s\n" + "https://www.youtube.com/watch?v=1cIzQ2xq3Kw\n" + "https://www.youtube.com/watch?v=heG18vkVJyo&t=32s\n" + "https://www.youtube.com/watch?v=mVAHph7QpJM\n" + "https://www.youtube.com/watch?v=FhQ9xSK0oiY\n" + "https://www.youtube.com/watch?v=Abctipv1Aqk\n" + "https://www.youtube.com/watch?v=9Kf3EZPUOkk\n" + "https://www.youtube.com/watch?v=PasZLvRYMR4\n" + "https://www.youtube.com/watch?v=keBU3oaEXBg\n" + "https://www.youtube.com/watch?v=5I1ms4q94uk\n" + "https://www.youtube.com/watch?v=gwfh4DuS7GQ\n" + "https://www.youtube.com/watch?v=xxRB6ozPgQM\n" + "https://www.youtube.com/watch?v=Zq6QfT3017M"; 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