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

/
/
igm

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 = "^((AT)(U\\d{8})|(BE)(0\\d{9})|(BG)(\\d{9,10})|(CY)(\\d{8}[LX])|(CZ)(\\d{8,10})|(DE)(\\d{9})|(DK)(\\d{8})|(EE)(\\d{9})|(EL|GR)(\\d{9})|(ES)([\\dA-Z]\\d{7}[\\dA-Z])|(FI)(\\d{8})|(FR)([\\dA-Z]{2}\\d{9})|(HU)(\\d{8})|(IE)(\\d{7}[A-Z]{2})|(IT)(\\d{11})|(LT)(\\d{9}|\\d{12})|(LU)(\\d{8})|(LV)(\\d{11})|(MT)(\\d{8})|(NL)(\\d{9}(B\\d{2}|BO2))|(PL)(\\d{10})|(PT)(\\d{9})|(RO)(\\d{2,10})|(SE)(\\d{12})|(SI)(\\d{8})|(SK)(\\d{10}))$"; final String string = "ATU12345678\n" + "BE0123456789\n" + "BG123456789\n" + "BG1234567890\n" + "CY12345678X\n" + "CY12345678L\n" + "CZ12345678\n" + "CZ123456789\n" + "CZ1234567890\n" + "DE123456789\n" + "DK12345678\n" + "EE123456789\n" + "EL123456789\n" + "GR123456789\n" + "ESX12345678\n" + "ES12345678X\n" + "ESX1234567X\n" + "FI12345678\n" + "FR12345678901\n" + "FRX1234567890\n" + "FR1X123456789\n" + "FRXX123456789\n" + "HU12345678\n" + "IE1234567WA\n" + "IE1234567FA\n" + "IT12345678901\n" + "LT123456789\n" + "LT123456789012\n" + "LU12345678\n" + "LV12345678901\n" + "MT12345678\n" + "NL123456789B01\n" + "NL123456789BO2\n" + "PL1234567890\n" + "PT123456789\n" + "RO1234567890\n" + "SE123456789012\n" + "SK1234567890"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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