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

/
/
gm

Test String

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 = "^([\"']?)(\\$?([0-9]{1,3},([0-9]{3},?)*[0-9]{3}|[0-9]{1,3})((.[0-9]{0,3})[0-9]{0,10})?)\\1$"; final String string = "123456\n" + "123.\n" + ".\n" + ".123\n" + "123.154574\n" + ".545.4584\n" + "+1454\n" + "+487.54587\n" + "-54587.7487\n" + ".1225-\n" + ".456+\n" + "454.4+\n" + "454.455874\n" + "45.45745687687.5678\n" + "45,547\n" + "45,5\n" + ",154567891021\n" + "0,154567891021\n" + "123,1023458748\n" + "4546587,54587867\n" + "578,4\n" + "0\n" + ".123\n" + "0.00145\n" + "0.0\n" + "012345678910\n" + "1,345.154\n" + "4,330,234.34\n" + "5.545445454\n" + "3,023,123.34\n" + "12.1\n" + "5,356.12345678910\n" + "1.20\n" + "1.01\n" + "0.52\n" + "125.30\n" + "158,265.36\n" + "100,100,100,123,125,568,000.00\n" + "\"\"\n" + "''\n" + "\"1\"\n" + "'1'\n" + "\"123\"\n" + "'123'\n" + "\"123.1\"\n" + "'0'\n" + "\"123.12345647891\"\n" + "\"19,741.24\"\n" + "1234567891023154546574568768767866876767676876584764646546546465465464564564.240\n" + "\"191741.240\""; 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