Poland PESEL Validator

Check a Polish PESEL with the official weighted check digit and read the sex it encodes. 100% local — your number is never uploaded. Built for Poland.

Result

Batch check — paste many, one per line

Validate a Polish PESEL

Paste an 11-digit PESEL to verify its check digit and read the sex it encodes. Everything runs locally in your browser.

PESEL is Poland's 11-digit personal identity number, maintained under the PESEL Act by the Ministry of Digital Affairs. It encodes date of birth (positions 1–6, with the month offset marking the century: +20 for 2000–2099, +40 for 2100s, +80 for 1800s), a serial number, sex (10th digit: odd = male, even = female), and a check digit. The checksum multiplies the first 10 digits by weights 1-3-7-9-1-3-7-9-1-3; the check digit is (10 − (sum mod 10)) mod 10. This tool validates the date (including the century offset), decodes sex and birth date, and recomputes the checksum — entirely in your browser.

A valid PESEL structure does not confirm the number was actually issued to anyone; only government records can. Never treat a format check as identity verification. Last verified: July 2026.

FAQ

How does PESEL encode someone born in 2004?

The month field gets +20: a person born 15 March 2004 has positions 1–6 = 042315 (04 year, 23 = March + 20, 15 day). Born in 1998, the same date would be 980315 with no offset.

Which digit tells the sex?

The 10th: odd digits (1,3,5,7,9) mean male, even digits (0,2,4,6,8) mean female. The tool decodes it for you.

What exactly does the checksum verify?

It catches single-digit typos and most transpositions. Weights 1,3,7,9 repeat across the first 10 digits; the sum plus the check digit must be divisible by 10.

Is validating a PESEL here GDPR-safe?

The number never leaves your device — validation is pure local math with no upload, logging or storage. Still, handle other people’s PESEL numbers only with a lawful basis; a batch check of employees is your responsibility as controller.