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 = "[!-\\/:-@[-`\\{-~]"; final String string = " ! U+0021 EXCLAMATION MARK\n" + " \" U+0022 QUOTATION MARK\n" + " # U+0023 NUMBER SIGN\n" + " $ U+0024 DOLLAR SIGN\n" + " % U+0025 PERCENT SIGN\n" + " & U+0026 AMPERSAND\n" + " ' U+0027 APOSTROPHE\n" + " ( U+0028 LEFT PARENTHESIS\n" + " ) U+0029 RIGHT PARENTHESIS\n" + " * U+002A ASTERISK\n" + " + U+002B PLUS SIGN\n" + " , U+002C COMMA\n" + " - U+002D HYPHEN-MINUS\n" + " . U+002E FULL STOP\n" + " / U+002F SOLIDUS\n" + " : U+003A COLON\n" + " ; U+003B SEMICOLON\n" + " < U+003C LESS-THAN SIGN\n" + " = U+003D EQUALS SIGN\n" + " > U+003E GREATER-THAN SIGN\n" + " ? U+003F QUESTION MARK\n" + " @ U+0040 COMMERCIAL AT\n" + " [ U+005B LEFT SQUARE BRACKET\n" + " \\ U+005C REVERSE SOLIDUS\n" + " ] U+005D RIGHT SQUARE BRACKET\n" + " ^ U+005E CIRCUMFLEX ACCENT\n" + " _ U+005F LOW LINE\n" + " ` U+0060 GRAVE ACCENT\n" + " { U+007B LEFT CURLY BRACKET\n" + " | U+007C VERTICAL LINE\n" + " } U+007D RIGHT CURLY BRACKET\n" + " ~ U+007E TILDE"; 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