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

`
`
gui

Test String

Substitution

Processing...

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?|(e)(pisodes?)|(c)(hapters?)|(c)(hs?)|(e)(ps?)|(c)(s?)|(e)(s?)|()())\\s*((\\d+(?:\\.\\d+)?(?:[A-Z]\\b)?)(?:\\s*(?:[,&+-]|and)\\s*(?:(?:e(?:pisodes?)|c(?:hapters?)|c(?:hs?)|e(?:ps?)|c(?:s?)|e(?:s?)|)\\s*)?(?4))*)"; final String string = "chapter 2A Hello \n" + "chapter 2AHello\n" + "text chapter 25.6 text\n" + " // c~25.6\n" + "text chapters 23, 24, 25 text\n" + " // c~23-25\n" + "text chapter 23, 25 text\n" + " // c~23 & 25\n" + "text chapter 23 & 24 & 25 text\n" + " // c~23-25\n" + "text c25.5-30 text\n" + " // c~25.5-30\n" + "text c99-c102 text\n" + " // c~99-102\n" + "text chapter 1 - 3 text\n" + " // c~1-3\n" + "33 text chapter 1, 2 text 3\n" + " // c~1-2\n" + "chapter 25.6 & chapter 29\n" + " // c~25.6 & 29\n" + "chapter 25+c26\n" + " // c~25-26\n" + "chapter 25 + 26 + 27\n" + " // c~25-27\n" + "chapter 10.4C\n" + " = c~10.4 part 3\n" + "chapter 2B\n" + " = c~2 part 2"; final String subst = ""; final Pattern pattern = Pattern.compile(regex, Pattern.UNICODE_CASE | Pattern.CASE_INSENSITIVE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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