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

/
/
guxm

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 = "(?(DEFINE)\n" + " (?<currency_symbol> \\p{Sc} )\n" + " (?<leading_group> [1-9] \\d{0,2}+ )\n" + " (?<group> \\d{3} )\n" + " (?<non_leading_groups> (?&group) (?:(?&group_delim)(?&group))*+ )\n" + " (?<decimal_delim>\n" + " (?# Use the opposite of group_delim. )\n" + " (?(group_delim_comma)\n" + " \\.\n" + " | (?(group_delim_period)\n" + " ,\n" + " | [,.] (?# There's no definitive grouping_delim. )\n" + " )\n" + " )\n" + " )\n" + ")\n\n" + "^\n" + "(?>\n" + " (?&currency_symbol)\n" + " (?&leading_group)\n" + " (?:\n" + " (?<group_delim>\n" + " (?<group_delim_comma> , ) |\n" + " (?<group_delim_period> \\. ) |\n" + " \\ (?# Allow whitespace as a delimiter. )\n" + " )\n" + " (?&non_leading_groups)\n" + " | \\d*+ (?# It's also possible that there's no delimiter. )\n" + " )\n" + ")\n" + "(?:\n" + " (?&decimal_delim)\n" + " \\d*+\n" + ")?+\n" + "$"; final String string = "We want to match these:\n" + "$1\n" + "$10\n" + "$100\n" + "$1000\n" + "$1,000\n" + "$10,000\n" + "$100,000\n" + "$1,000,000\n" + "$1.00\n" + "$100.00\n" + "$10,000.00\n" + "$1,000,000.00\n" + "$1.000.000,00\n" + "$1.000\n" + "$1.000.000\n" + "$1,00\n" + "$1.000,00\n" + "$10000000000000\n\n" + "We don't want to match these:\n" + "$1,000,00\n" + "$1,00,00\n" + "$1.00.000\n\n" + "A few different currency symbols that we want to match:\n" + "$1\n" + "¢1\n" + "£1\n" + "¤1\n" + "¥1\n" + "₠1\n" + "₡1\n" + "₢1\n" + "₣1\n" + "₤1\n" + "₥1\n" + "₦1\n" + "₧1\n" + "₩1\n" + "₪1\n" + "₫1\n" + "€1\n" + "₭1\n" + "₮1\n" + "₯1\n" + "₰1\n" + "₱1\n" + "₲1\n" + "₳1\n" + "₴1\n" + "₵1\n" + "₶1\n" + "₷1\n" + "₸1\n" + "₹1\n" + "₺1\n" + "₻1\n" + "₼1\n" + "₽1\n\n" + "Nearby symbols that share some bytes (UTF-8) that we don't want to match:\n" + "¡1\n" + "¦1\n" + "§1\n" + "©1\n" + "ₔ1"; final Pattern pattern = Pattern.compile(regex, Pattern.UNICODE_CASE | Pattern.COMMENTS | 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