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 = "s='(?<img>[^']+)';\\w+\\s\\w+=\\['(?<id>\\w+_\\d+)'];"; final String string = "<script nonce=\"cRlsgv0sADvnNakDIZj-4w\">(function(){var s='data:image/png;base64,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\\x3d';var ii=['wp_thbn_66'];_setImagesSrc(ii,s);})();</script>"; 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