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

r"
"
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 = "\\b(?:DE|AT)(?: ?[0-9]){18}(?:(?: ?[0-9]){2})?\\b"; final String string = "################## Germany IBAN ##################\n" + "DE89 3704 0044 0532 0130 00\n" + "DE59290501010001149590\n" + "DE62500105179628448387\n" + "DE55500105172374652131\n" + "DE50500105176152274153\n" + "IBAN: DE59290501010001149590\n\n\n" + "DE 0712 3412 3412 3412 3412\n" + "DE07 1234 1234 1234 1234 12\n" + "DE07 1234 1234 1234 123412\n\n" + "Mashine friendly DE07123412341234123412 style\n" + "This format DE07 1234 1234 1234 1234 12 is given by DIN\n" + "Human DE07 1234 1234 1234 123412 readable\n" + "Not good DE07 12341234 1234123412 readable\n\n" + "################## Austrian IBAN ##################\n" + "AT61 1904 3002 3457 3201\n" + "AT59290501010001149590\n" + "AT62500105179628448387\n" + "AT55500105172374652131\n" + "AT50500105176152274153\n\n" + "AT 0712 3412 3412 3412 3412\n" + "AT07 1234 1234 1234 1234 12\n" + "AT07 1234 1234 1234 123412\n\n" + "Mashine friendly AT07123412341234123412 style\n" + "This format AT07 1234 1234 1234 1234 12 is given by DIN\n" + "Human AT07 1234 1234 1234 123412 readable\n" + "Not good AT07 12341234 1234123412 readable\n\n" + "################## Not Valid IBAN ##################\n" + "USt-IdNr.: DE310453183\n" + "eingetragen \n\n" + "Tax number: DE310453183\n" + "eingetragen\n\n" + "Tax number: DE310453183eingetragen\n\n" + "Tax number: AT310453183introduce\n\n"; 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