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

/
/
gm

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 = "^([A-Z]{2}[ \\-]?[0-9]{2})(?=(?:[ \\-]?[A-Z0-9]){9,30}$)((?:[ \\-]?[A-Z0-9]{3,5}){2,7})([ \\-]?[A-Z0-9]{1,3})?$"; final String string = "XX00 1234 5678 9012 3456 7890 1234 5678 90\n" + "YY00123456789012345678901234567890\n" + "----\n" + "AL28 BBB SSSSK CCCC CCCC CCCC CCCC\n" + "AD24-BBBB-SSSS-CCCC-CCCC-CCCC\n" + "BE16 BBBC CCCC CCKK\n" + "BA20 BBBS SSCC CCCC CCKK\n" + "BG22-BBBB-SSSS-DDCC-CCCC-CC\n" + "CY28 BBBS SSSS CCCC CCCC CCCC CCCC\n" + "DK18 BBBB CCCC CCCC CC\n" + "DE22 BBBB BBBB CCCC CCCC CC\n" + "EE20 BBSS CCCC CCCC CCCK\n" + "FO18 CCCC CCCC CCCC CC\n" + "FI18 BBBB BBCC CCCC CK\n" + "FR27 BBBB BSSS SSCC CCCC CCCC CKK\n" + "GE22 BBCC CCCC CCCC CCCC CC\n" + "GI23 BBBB CCCC CCCC CCCC CCC\n" + "GR27 BBBS SSSC CCCC CCCC CCCC CCC\n" + "GL18 BBBB CCCC CCCC CC\n" + "HU28 BBBS SSSK CCCC CCCC CCCC CCCK\n" + "IE22 BBBB SSSS SSCC CCCC CC\n" + "IS26 BBBB TTCC CCCC XXXX XXXX XX\n" + "IL23 BBB SSS CCCCCCCCCCCCC\n" + "IT27 KBBB BBSS SSSC CCCC CCCC CCC\n" + "JO27 BBBB CCCC CCCC CCCC CCCC CCCC CC\n" + "HR21 BBBB BBBC CCCC CCCC C\n" + "LV21 BBBB CCCC CCCC CCCC C\n" + "LB28 BBBB CCCC CCCC CCCC CCCC CCCC CC\n" + "LI21 BBBB BCCC CCCC CCCC C\n" + "LT20 BBBB BCCC CCCC CCCC\n" + "LU20 BBBC CCCC CCCC CCCC\n" + "MK19 BBBC CCCC CCCC CKK\n" + "MT31 BBBB SSSS SCCC CCCC CCCC CCCC CCC\n" + "MU30 BBBB BBSS CCCC CCCC CCCC RRRD DD\n" + "MC27 BBBB BSSS SSCC CCCC CCCC CKK\n" + "ME22 BBBC CCCC CCCC CCCC KK\n" + "NL18 BBBB CCCC CCCC CK\n" + "NO15 BBBB CCCC CCK\n" + "AT20 BBBB BCCC CCCC CCCC\n" + "PL28 BBBS SSSK CCCC CCCC CCCC CCCC\n" + "PT25 BBBB SSSS CCCC CCCC CCCK K\n" + "RO24 BBBB CCCC CCCC CCCC CCCC\n" + "SM27 KBBB BBSS SSSX XXXX XXXX XXX\n" + "SA24 BBCC CCCC CCCC CCCC CCCC\n" + "RS22 BBBC CCCC CCCC CCCC KK\n" + "SK24 BBBB SSSS SSCC CCCC CCCC\n" + "SI19 BBSS SCCC CCCC CKK\n" + "ES24 BBBB SSSS KKCC CCCC CCCC\n" + "CZ24 BBBB SSSS SSCC CCCC CCCC\n" + "TR26 BBBB BRCC CCCC CCCC CCCC CC\n" + "TN24 BBBB BCCC CCCC CCCC CCCC\n" + "GB22 BBBB SSSS SSCC CCCC CC\n" + "AE23 BBBB SSSS CCCC CCCC CCC\n" + "SE24 BBBB CCCC CCCC CCCC CCCC\n" + "CH21 BBBB BCCC CCCC CCCC C"; 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