PESEL validator - check a Polish PESEL number

PESEL is the Polish national identification number, kept in the central population register. Every Polish citizen has one from birth, and foreigners get one when they register their residence in Poland (meldunek) or apply for it because they need it - for example to work, to be insured with ZUS, to use the public health service or to set up a Trusted Profile for e-government. Since 2022 many Ukrainian citizens have received PESEL numbers under special rules as well.

Employers, banks, doctors and offices ask for it constantly, so a typo in a form is a common source of rejected applications. This validator catches most such mistakes before you submit.

PESEL has 11 digits in the pattern YYMMDDZZZXQ:

• YYMMDD - the date of birth (last two digits of the year, month, day),
• ZZZX - a serial number; its last digit (the 10th digit of PESEL) shows sex: even for women, odd for men,
• Q - the check digit.

The century of birth is encoded in the month:

Multiply the first 10 digits by the weights 1, 3, 7, 9, 1, 3, 7, 9, 1, 3 and add the results. The check digit is (10 - sum mod 10) mod 10.

Example for 44051401359: 4·1 + 4·3 + 0·7 + 5·9 + 1·1 + 4·3 + 0·7 + 1·9 + 3·1 + 5·3 = 101. The remainder of 101 divided by 10 is 1, so the check digit is 10 - 1 = 9, which matches the last digit. The number belongs to a man (10th digit 5 is odd) born on 14 May 1944.

Second example: in 05231712342 the month 23 means March 2005 (23 - 20 = 3), and the 10th digit 4 means a woman.

The validator checks formal correctness only: the length, whether the date exists and the checksum. It does not connect to the PESEL register, so it cannot confirm that the number was ever issued or who it belongs to. Only authorised institutions can query the register. Everything is computed locally in your browser, so the numbers you type are never sent or stored. For other Polish identifiers use the NIP validator or the REGON validator.