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

r"
"
gmu

Test String

Substitution

Processing...

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 = "[\\u00B2\\u00B3\\u00B9\\u00BC-\\u00BE\\u09F4-\\u09F9\\u0B72-\\u0B77\\u0BF0-\\u0BF2\\u0C78-\\u0C7E\\u0D58-\\u0D5E\\u0D70-\\u0D78\\u0F2A-\\u0F33\\u1369-\\u137C\\u17F0-\\u17F9\\u19DA\\u2070\\u2074-\\u2079\\u2080-\\u2089\\u2150-\\u215F\\u2189\\u2460-\\u249B\\u24EA-\\u24FF\\u2776-\\u2793\\u2CFD\\u3192-\\u3195\\u3220-\\u3229\\u3248-\\u324F\\u3251-\\u325F\\u3280-\\u3289\\u32B1-\\u32BF\\uA830-\\uA835\\U00010107-\\U00010133\\U00010175-\\U00010178\\U0001018A\\U0001018B\\U000102E1-\\U000102FB\\U00010320-\\U00010323\\U00010858-\\U0001085F\\U00010879-\\U0001087F\\U000108A7-\\U000108AF\\U000108FB-\\U000108FF\\U00010916-\\U0001091B\\U000109BC\\U000109BD\\U000109C0-\\U000109CF\\U000109D2-\\U000109FF\\U00010A40-\\U00010A47\\U00010A7D\\U00010A7E\\U00010A9D-\\U00010A9F\\U00010AEB-\\U00010AEF\\U00010B58-\\U00010B5F\\U00010B78-\\U00010B7F\\U00010BA9-\\U00010BAF\\U00010CFA-\\U00010CFF\\U00010E60-\\U00010E7E\\U00011052-\\U00011065\\U000111E1-\\U000111F4\\U0001173A\\U0001173B\\U000118EA-\\U000118F2\\U00011C5A-\\U00011C6C\\U00016B5B-\\U00016B61\\U0001D360-\\U0001D371\\U0001E8C7-\\U0001E8CF\\U0001F100-\\U0001F10C\\W\\d_]+"; final String string = "Room: 25m²\", \"I have eaten ¼ of the cake."; final String subst = " "; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.UNICODE_CASE); 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