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

/
/
sg

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 = "\\<li\\>[^<]*?(Fandoms).*?\\<\\/li\\>"; final String string = "<p>by <a rel=\"author\" href=\"/users/Ellixerff/pseuds/Ellixerff\">Ellixerff</a></p>\n" + "<p>It's happened before, but this time is different. Can the consequences of bringing the one you love back, cost you ev fin story.</p>\n" + "<p>Words: 8003, Chapters: 7/7, Language: English</p>\n" + "<ul>\n" + " <li>Fandoms: <a full_pat class=\"tag\" href=\"https://archiveofourown.org/tags/Xena:%20Warrior%20Princess/works\">Xeni Princess</a></li>\n" + " <li>Rating: <a full_path=\"true\" class=\"tag\" href=\"https://archiveofourown.org/tags/Mature/works\">Mature</a></li>\n" + " <li>Warnings: <a full_f class=\"tag\" href=\"https://archiveofourown.org/tags/Choose\"> Chose Not To Use Archive Warnings</a></li>\n" + " <li>Categories: <a full_path=\"true\" class=\"tag\" href=\"https://archiveofourown.org/tags/F*s*F/works\">F/F</a></li>\n" + " <li>Characters: <a full_path=\"true\" href=\"https://archiveofourown.org/tags/Gabrielle%20(Xena)/works\">Gabrielle (Xena)</a></li>\n" + " <li><a fi class=\"tag\" href=\"https://archiveofourown.org/tags/Xena%20(Xena)/works\">Xena (Xena)</a></li>\n" + " <li>Relationships: <a full_path=\"true\" class=\"tag\" href=\"https://archiveofourown.org/tags/Gabrielle*s*Xena/works\">Gabrielle/Xena</a></li>\n" + "</ul>\n"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); 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