International · Validation
Norwegian organisasjonsnummer validator.
Check a 9-digit Norwegian organisasjonsnummer (org.nr): length and modulus-11 check digit, including the NO ... MVA form. Format and checksum only.
How it works: Brønnøysund Register Centre defines the number as 9 digits, the last a check digit. The first eight digits are multiplied by 3, 2, 7, 6, 5, 4, 3, 2 and summed; the check digit is 11 minus the remainder after dividing by 11 (0 if the remainder is 0). If that would be 10, the number is invalid.
Inputs
Result
Enter a number and press Check.
How the organisasjonsnummer is built
Brønnøysundregistrene states that the organisation number consists of 9 digits and that the last is a check digit. For entities in the VAT register, it says the VAT number is the same as the organisation number; in invoices it is conventionally written NO 123 456 785 MVA.
| Step | Rule |
|---|---|
| 1 | Multiply digits 1–8 by 3, 2, 7, 6, 5, 4, 3, 2 |
| 2 | Add the products and divide by 11 |
| 3 | Check digit = 11 − remainder (0 if the remainder is 0) |
| 4 | If the result would be 10, the number is invalid |
Worked example from Brønnøysund itself: 12345678 has weighted sum 138, remainder 6, check digit 11 − 6 = 5, giving 123456785. python-stdnum’s example 988 077 917 sums to 198 (nine digits, weights 3 2 7 6 5 4 3 2 1), which is divisible by 11.
Format and checksum only — not a registry lookup
A well-formed number may still be unissued. Use the Enhetsregisteret to confirm the entity. Nothing you type leaves your browser.
Norwegian Organisasjonsnummer FAQ
How many digits is a Norwegian organisasjonsnummer?
Nine, the last being a modulus-11 check digit. VAT-registered entities use the same number, written with MVA.
What if the check calculation gives 10?
Then no valid organisasjonsnummer exists with those first eight digits, because 10 cannot be one digit.
Does this confirm a company exists?
No. It checks format and arithmetic only. Search the official Enhetsregisteret on brreg.no to confirm a real entity.
Official register
To confirm a number is real, use the official source: Enhetsregisteret (Brønnøysund Register Centre). Search the Central Coordinating Register for Legal Entities on brreg.no to confirm a number belongs to a real entity.
Sources
- Brønnøysundregistrene, About the organisation number (9 digits, weights 3 2 7 6 5 4 3 2, 11 minus remainder, 10 invalid, example 123456785); retrieved October 2026
- python-stdnum, stdnum/no/orgnr.py (equivalent all-nine-digit form and the 988 077 917 doctest); retrieved October 2026
Privacy and scope
This tool runs entirely in your browser: nothing you type is transmitted, stored, or logged, and it queries no government or commercial register. It checks format and checksum only and does not imply any official verification. Do not enter identity numbers belonging to other people that you have no reason to hold.