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?:\\/\\/(?:open\\.)?spotify.com\\/(user|episode|playlist|track)\\/(?:spotify\\/playlist\\/)?(\\w*)"; final String string = "https://open.spotify.com/user/spotify/playlist/37i9dQZF1DZ06evO2ZpGiQ?si=-6S0EBlURrao__YyIOW6bg\n\n" + "https://open.spotify.com/episode/0aib8d7Hi7N9Td6eVKliWC?si=8f846b406a844873\n" + "https://open.spotify.com/playlist/7Kk0KvfzcaX4QLtli1rIBK\n" + "https://open.spotify.com/track/6PEd4IINRYCvjDXfKxO0pE?si=8f3fae6b22d64006\n" + "https://open.spotify.com/playlist/7Kk0KvfzcaX4QLtli1rIBK?si=dde5fbdbe97c4cfc\n\n\n\n" + "https://spotify.com/user/spotify/playlist/37i9dQZF1DZ06evO2ZpGiQ?si=-6S0EBlURrao__YyIOW6bg\n\n" + "https://spotify.com/episode/0aib8d7Hi7N9Td6eVKliWC?si=8f846b406a844873\n" + "https://spotify.com/playlist/7Kk0KvfzcaX4QLtli1rIBK \n" + "https://spotify.com/track/6PEd4IINRYCvjDXfKxO0pE?si=8f3fae6b22d64006\n" + "https://spotify.com/playlist/7Kk0KvfzcaX4QLtli1rIBK?si=dde5fbdbe97c4cfc\n\n\n" + "spotify:user:spotify:playlist:37i9dQZF1DZ06evO2ZpGiQ"; 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