Denmark (DK)
Danish VAT Number Validation
Format, pattern, and MOD 11 checksum algorithm for DK VAT numbers
Danish VAT numbers (CVR-nummer) consist of 8 digits and use a weighted MOD 11 checksum algorithm. The CVR number also serves as the general business identifier.
Format vs. Active Validation
This checks format only, not if a VAT number is really registered. Use VatDB's API to verify is a number is really registered and active. VatDB checks official EU and national datasources.
Format Overview
| Property | Value |
|---|---|
| Country Code | DK |
| Format | 8 digits |
| Length | 8 digits |
| Example | DK12345678 |
Regex Pattern
^DK[0-9]{8}$
Checksum Algorithm (MOD 11)
def validate_dk_vat(number):
if number.startswith('DK'):
number = number[2:]
if len(number) != 8 or not number.isdigit():
return False
weights = [2, 7, 6, 5, 4, 3, 2, 1]
total = sum(int(d) * w for d, w in zip(number, weights))
return total % 11 == 0
The weighted sum must be divisible by 11 for the number to be valid.
Frequently Asked Questions
How do I verify a Danish VAT number (CVR)?
Danish VAT numbers use MOD 11 validation with weights [2,7,6,5,4,3,2,1]. The weighted sum must be divisible by 11. Use VatDB's API for official verification against EU and Danish CVR databases.
What does a Danish VAT number look like?
A Danish VAT number has the format DK12345678 - 'DK' followed by exactly 8 digits. This number is also the company's CVR number.
How many digits are in a Danish VAT number?
A Danish VAT number contains exactly 8 digits after the DK country code. The complete number is 10 characters: DK + 8 digits.
What is a Danish CVR number?
CVR (Det Centrale Virksomhedsregister) is the Danish Central Business Register number. It serves as both the company registration number and VAT number. All Danish VAT numbers are CVR numbers.
Can I look up a Danish company by CVR number?
Yes, you can look up Danish company details on cvr.dk, the official Central Business Register. Enter the 8-digit CVR/VAT number to see company name, address, status, and more.
Where can I check if a Danish VAT number is valid?
Check VAT numbers using VatDB's API for real-time validation against official EU and national databases, with company details included.
What's the difference between format validation and checking if a VAT number is active?
Format validation is offline - it doesn't query any database. A valid-looking number might not exist or could be inactive. VatDB performs real-time lookups to confirm genuine registration.