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

/
/

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 = "^AL\\d{10}[0-9A-Z]{16}$|^AD\\d{10}[0-9A-Z]{12}$|^AT\\d{18}$|^BH\\d{2}[A-Z]{4}[0-9A-Z]{14}$|^BE\\d{14}$|^BA\\d{18}$|^BG\\d{2}[A-Z]{4}\\d{6}[0-9A-Z]{8}$|^HR\\d{19}$|^CY\\d{10}[0-9A-Z]{16}$|^CZ\\d{22}$|^DK\\d{16}$|^FO\\d{16}$|^GL\\d{16}$|^DO\\d{2}[0-9A-Z]{4}\\d{20}$|^EE\\d{18}$|^FI\\d{16}$|^FR\\d{12}[0-9A-Z]{11}\\d{2}$|^GE\\d{2}[A-Z]{2}\\d{16}$|^DE\\d{20}$|^GI\\d{2}[A-Z]{4}[0-9A-Z]{15}$|^GR\\d{9}[0-9A-Z]{16}$|^HU\\d{26}$|^IS\\d{24}$|^IE\\d{2}[A-Z]{4}\\d{14}$|^IL\\d{21}$|^IT\\d{2}[A-Z]\\d{10}[0-9A-Z]{12}$|^[A-Z]{2}\\d{5}[0-9A-Z]{13}$|^KW\\d{2}[A-Z]{4}22!$|^LV\\d{2}[A-Z]{4}[0-9A-Z]{13}$|^LB\\d{6}[0-9A-Z]{20}$|^LI\\d{7}[0-9A-Z]{12}$|^LT\\d{18}$|^LU\\d{5}[0-9A-Z]{13}$|^MK\\d{5}[0-9A-Z]{10}\\d{2}$|^MT\\d{2}[A-Z]{4}\\d{5}[0-9A-Z]{18}$|^MR13\\d{23}$|^MU\\d{2}[A-Z]{4}\\d{19}[A-Z]{3}$|^MC\\d{12}[0-9A-Z]{11}\\d{2}$|^ME\\d{20}$|^NL\\d{2}[A-Z]{4}\\d{10}$|^NO\\d{13}$|^PL\\d{10}[0-9A-Z]\\{,16\\}n$|^PT\\d{23}$|^RO\\d{2}[A-Z]{4}[0-9A-Z]{16}$|^SM\\d{2}[A-Z]\\d{10}[0-9A-Z]{12}$|^SA\\d{4}[0-9A-Z]{18}$|^RS\\d{20}$|^SK\\d{22}$|^SI\\d{17}$|^ES\\d{22}$|^SE\\d{22}$|^CH\\d{7}[0-9A-Z]{12}$|^TN59\\d{20}$|^TR\\d{7}[0-9A-Z]{17}$|^AE\\d{21}$|^GB\\d{2}[A-Z]{4}\\d{14}$"; final String string = "NL39INGB0044332211"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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