How is the org-number check digit calculated?

The first eight digits are multiplied by the weights 3, 2, 7, 6, 5, 4, 3, 2 and summed. The sum modulo 11 gives a remainder; the check digit is 11 minus that remainder, or 0 if the remainder is 0.

What if the remainder is 1?

If the modulo-11 remainder is exactly 1, no valid check digit can be formed, so that combination of eight digits was never issued. The tool reports the number as invalid in that case.

Do I have to include the MVA suffix?

No. You can enter just the 9-digit org number. The tool validates the check digit and shows the canonical VAT form with the MVA suffix added, since the suffix is required when the number is used for VAT.

Is my number sent to a server?

No. The modulo-11 check runs entirely in your browser. Nothing is transmitted, so the tool is safe for compliance and accounting use.

Norway MVA (VAT) Number Validator

The Norway MVA Validator checks whether a Norwegian VAT number is structurally valid by recomputing the modulo-11 check digit of the 9-digit organisation number and confirming the MVA suffix. It accepts the number with or without the suffix and shows the canonical VAT form — all in your browser.

How it works

A Norwegian VAT number is the 9-digit organisation number (organisasjonsnummer) followed by the suffix MVA, for example 123456785MVA. The org number carries a modulo-11 check digit that catches transposed or mistyped figures.

The tool multiplies the first eight digits by the weights [3,2,7,6,5,4,3,2] and sums the products. Taking the sum modulo 11 gives a remainder. If the remainder is 0, the check digit should be 0; if it is 1, no valid check digit exists and the number is invalid; otherwise the expected check digit is 11 minus the remainder, and it must equal the ninth digit. The tool then renders the number in its canonical VAT form with the MVA suffix.

Example

For 123456785 the tool derives the expected check digit from the first eight digits and compares it to the trailing 5. If they match, the org number is internally consistent, and the tool displays 123456785 MVA as the VAT form.

Notes

A valid check digit confirms the org number is internally consistent — it does not confirm the entity is currently VAT-registered. For VAT the number must carry the MVA suffix, and live status should be checked in the Brønnøysund Register (Enhetsregisteret). Everything runs locally in your browser.