International · Validation
Swedish personnummer validator.
Check a Swedish personnummer or samordningsnummer against its Luhn check digit and see the birth date it encodes. It checks format and checksum only and cannot confirm a number was issued to anyone. Everything runs in your browser.
How it works: a personnummer is YYMMDD-NNNC (or YYYYMMDD-NNNC). The last digit is a Luhn check digit over the first nine of the 10-digit form; if it does not match, the number has a typo.
Inputs
Result
Enter a personnummer and press Check.
How a Swedish personnummer is built
A personnummer is written YYMMDD-NNNC (10 digits) or YYYYMMDD-NNNC (12 digits).
| Part | Meaning |
|---|---|
| YYMMDD | Date of birth (year, month, day) |
| - or + | Hyphen normally; it becomes a plus sign the year the person turns 100 |
| NNN | Birth number; the last digit is odd for legal sex male and even for female |
| C | Check digit, calculated with the Luhn algorithm |
The Luhn check is run on the 10-digit form. The first nine digits are multiplied by 2,1,2,1,2,1,2,1,2, any two-digit product is reduced to the sum of its digits, and the check digit is 10 minus the last digit of the total (0 if that is 10). For a 12-digit number the first two digits are dropped first.
A samordningsnummer (coordination number) has the same layout, but 60 is added to the day of birth, so the day reads 61 to 91. This tool subtracts 60 before checking the date and labels the result.
With only two year digits, the century comes from the separator: with "-" the tool picks the most recent past year matching the two digits, and with "+" it goes back one further century. A 12-digit number states its own year.
Checksum and format only, not a Skatteverket lookup
A passing result means the number is internally consistent. It cannot confirm the number was issued or belongs to anyone; only Skatteverket holds that register. The sex digit is shown as the registered digit parity, nothing more.
Sources
Structure, sex digit, check digit and the "+" rule: Skatteverket, Personnummer. Luhn weighting, 12-digit rule and samordningsnummer (day + 60): Wikipedia: Personal identity number (Sweden). Independent implementation used to cross-check the algorithm and test numbers: python-stdnum, stdnum/se/personnummer.py.
Format and checksum only — not a register lookup
This tool checks the number entirely in your browser. It does not query Skatteverket, and a valid result is not proof the number was ever issued or belongs to anyone. Nothing you type is transmitted, stored, or logged.