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?:\\/\\/)?(www.)?((player.vimeo.com\\/video\\/[0-9]{9})|((youtube.com|youtu\\.be)\\/embed\\/([\\w-]{9,11})))"; final String string = "http://www.youtube.com/watch?v=GKnQGP67Xd0\n" + "https://www.youtube.com/watch?v=GKnQGP67Xd0\n" + "https://www.youtube.com/watch?v=GKnQGP67Xd0\n" + "https://www.youtube.com/watch?v=GKnQGP67Xd0\n" + "https://vimeo.com/662065137\n" + "https://vimeo.com/662065137\n" + "https://www.youtube.com/c/riotgamesmusic\n" + "https://vimeo.com/662065137\n" + "https://youtu.be/aXUCHNaZkWo\n" + "https://vimeo.com/662065137\n" + "https://vimeo.com/baconbaconbacon\n" + "https://www.youtube.com/channel/UCG_wKjFPEpdHf1Q6bTdE2JA\n" + "https://player.vimeo.com/video/662065137\n\n" + "última formato corto: http://youtu.be/NLqAF9hrVbY\n" + "iframe: http://www.youtube.com/embed/NLqAF9hrVbY\n" + "iframe (seguro): https://www.youtube.com/embed/NLqAF9hrVbY\n" + "objeto param: http://www.youtube.com/v/NLqAF9hrVbY?fs=1&hl=en_US\n" + "objeto de incrustación: http://www.youtube.com/v/NLqAF9hrVbY?fs=1&hl=en_US\n" + "ver: http://www.youtube.com/watch?v=NLqAF9hrVbY\n" + "usuarios: http://www.youtube.com/user/Scobleizer#p/u/1/1p3vcRhsYGo\n" + "ytscreeningroom: http://www.youtube.com/ytscreeningroom?v=NRHVzbJVx8I\n" + "cualquier cosa vale!: http://www.youtube.com/sandalsResorts#p/c/54B8C800269D7C1B/2/PPS-8DMrAn4\n" + "cualquier/subdominio/: http://gdata.youtube.com/feeds/api/videos/NLqAF9hrVbY\n" + "más params: http://www.youtube.com/watch?v=spDj54kf-vY&feature=g-vrec\n" + "la consulta puede tener el punto: http://www.youtube.com/watch?v=spDj54kf-vY&feature=youtu.be"; 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