Home personnummer Sweden
Sweden personnummer validator
How the personnummer format works
- Format
- 10 digits
- Example
- 8501151230
Things to watch for
- 10 digits validated with the Luhn algorithm — the same checksum used on payment cards, applied here to a personal identity number
- The full personnummer is often written with a hyphen (or a plus sign, for people over 100) before the last four digits — this tool checks the 10 core digits only
- Checksum only — a number passing this test does not confirm it is registered with Skatteverket or belongs to a real person
^[0-9]{10}$A personnummer is Sweden’s 10-digit personal identity number, issued by Skatteverket (the Swedish Tax Agency) to residents and used everywhere from opening a bank account to picking up a prescription or logging into a government e-service. It’s usually written with the last 4 digits set off by a hyphen — or a plus sign once the holder turns 100 — but the underlying value checked here is 10 plain digits.
Like several of its Nordic neighbors, a personnummer is built from real information: the first 6 digits are a birth date (YYMMDD), and the next 3 form a serial number assigned in sequence, whose last digit is odd for men and even for women. What sets it apart structurally is the checksum — rather than a bespoke national formula, Sweden validates the final digit with the Luhn algorithm, the same general-purpose check-digit method used on payment cards and many other identifiers worldwide.
How this validator works
This tool confirms the input is 10 digits, then runs the standard Luhn calculation — doubling every second digit from the right and summing the results — to confirm the final digit matches. It runs entirely in your browser, with nothing transmitted or stored.
What a pass doesn’t tell you
A pass means the 10 digits satisfy the Luhn checksum — it doesn’t confirm the personnummer was ever assigned by Skatteverket or is currently active. Only Skatteverket’s own records can confirm a specific number is genuinely on file.
Scope: this page covers the 10-digit personnummer’s format and Luhn checksum only — not the 12-digit century variant, and not identity or registration verification. Because it encodes a date of birth, treat a pass as a typo-check on the digits, nothing more.
Content last reviewed 2026-07-23.
personnummer FAQ
What do the 10 digits of a personnummer encode?
The first 6 digits are a date of birth (YYMMDD), and the last 4 form a serial: three digits assigned in sequence, followed by a Luhn check digit. The digit right before that final check digit also carries meaning — it's odd for men and even for women.
Why does this tool use the Luhn algorithm — isn't that for payment cards?
Luhn is best known from card numbers, but it's a general-purpose checksum, and Sweden uses that same algorithm to validate the personnummer. It works the same way here: doubling every second digit from the end and summing the results to confirm the final digit is correct.
What about the 12-digit personnummer that includes a century?
Skatteverket also issues a 12-digit form that spells out the full century (for example 198501151230) instead of a 2-digit year. This tool validates the 10-digit core — the version most commonly printed on ID cards and requested on forms — not the 12-digit variant.