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
Processing...

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 = "^(&amp;|also|a|about|again|all|after|are(nt)?|arent|as|an(y)?|at|\n" + " bcuz|before|be(low)?|between|bring|but|by|and|can(not)?|close(d)?|could(nt)?|\n" + " cuz|do(nt)?|down|decide(d)?|decision|on(to)?|or|of|our|over|out|have(nt)?|he(re)?|\n" + " her|his|other(s)?|even|got(ten)?|for|from|get(s)?|got(ten)?|has(nt)?|havent|he(s)?|\n" + " him|his|if|in|to|in(to)?|is(nt)?||make|me|once|play(ed)?|role|say(s)?|seen|she(s)?|\n" + " should(nt)?|stop(ped)?|time|my|no(t)?|must(nt)?|now|you(re)?|your|want|want(ed)?|\n" + " watch(ed)?|way|we(re)?|will|with||i|a|is(nt)?|just|would(nt)?|before|that|the(re)?|\n" + " their|them|they|this|turn|when|at|how|it(s)?|which|who|after|then|if|how|because|know(s)?|\n" + " yet|[A-Za-z]{1,2}|http(s)?://.*|www\\..*)$"; final String string = "why should havent also a yet their"; final Pattern pattern = Pattern.compile(regex, Pattern.COMMENTS); 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