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.)?instagram.com\\/?([a-zA-Z0-9\\.\\_\\-]+)?\\/([p]+)?([reel]+)?([tv]+)?([stories]+)?\\/([a-zA-Z0-9\\-\\_\\.]+)\\/?([0-9]+)?"; final String string = "// Group 2\n" + "https://www.instagram.com/p/CKYJRXVnwMO/?utm_source=ig_web_copy_link\n" + "instagram.com/p/CKYJRXVnwMO\n" + "www.instagram.com/p/CKYJRXVnwMO\n" + "https://www.instagram.com/taiga765/p/CYS-O2Gr8xZ/?utm_medium=copy_link\n" + "https://www.instagram.com/y.uuno/p/CXR5ATPls5M/?utm_medium=copy_link\n" + "// Group 3\n" + "http://www.instagram.com/reel/CRftq6QgG89/?utm_source=ig_web_copy_link\n" + "instagram.com/reel/CRftq6QgG89/\n" + "www.instagram.com/reel/CRftq6QgG89/\n" + "https://www.instagram.com/reel/CXR2xvbgCKW/?utm_medium=copy_link\n" + "// Group 4\n" + "https://www.instagram.com/tv/CN4RZWGn5wS/?utm_source=ig_web_copy_link\n" + "instagram.com/tv/CN4RZWGn5wS/\n" + "www.instagram.com/tv/CN4RZWGn5wS/\n" + "// Group 5\n" + "https://www.instagram.com/stories/sintha_tatha/2725190842360050880/\n" + "https://www.instagram.com/stories/urkawaiibae/2725982322342818754/\n" + "https://www.instagram.com/stories/willypangestu_/2725773180739197900/\n" + "https://www.instagram.com/stories/atrisna477769/\n\n" + "https://www.instagram.com/stories/highlights/17910460144693951/\n" + "www.instagram.com/stories/highlights/17879710684406193/\n" + "instagram.com/stories/highlights/17879710684406193/"; 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