Serbia JMBG validator
How the JMBG format works
- Format
- 13 digits
- Example
- 1905983710332
Things to watch for
- 13 digits with a weighted mod-11 check on the final digit
- The first 7 digits encode a date of birth and the next 2 a region — we validate format and checksum only, never the date or region, and never store what you enter
- Checksum only — a valid JMBG does not confirm the number is currently issued to a real person
^[0-9]{13}$JMBG — Jedinstveni matični broj građana, or Unique Master Citizen Number (Јединствени матични број грађана) — is the 13-digit identifier every Serbian citizen is assigned, issued by the Ministarstvo unutrašnjih poslova (MUP). It’s still in everyday active use: it appears on the national ID card and passport, and gets quoted for banking, payroll, healthcare, and school enrollment.
The 13 digits break down into a 7-digit date of birth, a 2-digit region code, a 3-digit sequence number, and a single check digit at the end. Serbian JMBGs typically carry a region code in the 70-99 range, a holdover from how the old Yugoslav numbering space was split among its constituent regions.
How this validator works
The check digit isn’t arbitrary: multiply each of the first 12 digits by a fixed weight, add the products together, and subtract the sum’s remainder after dividing by 11 from 11. If that leaves 10 or 11, the check digit is defined as 0; any other result becomes the check digit itself. This tool reruns that exact arithmetic in your browser and compares it to the 13th digit you entered — because the weights differ by position, a single mistyped or transposed digit almost always produces a mismatch.
What a pass doesn’t tell you
A matching check digit confirms the number is internally consistent — not that it’s currently assigned to a real person, or that the birth date and region it encodes are genuine. We don’t attempt to decode either.
Scope: this page covers JMBG format and checksum validation only — not identity or registry lookups. Nothing you type is sent to a server, stored, or logged.
Content last reviewed 2026-08-09.
JMBG FAQ
What does JMBG stand for, and who issues it in Serbia?
JMBG is short for Jedinstveni matični broj građana (Unique Master Citizen Number, Јединствени матични број грађана). In Serbia it's issued by the Ministarstvo unutrašnjih poslova (MUP) and used across identity documents, healthcare, banking, and employment records.
What do the digits in a Serbian JMBG represent?
The first seven digits encode a date of birth, the next two are a region code (Serbian JMBGs typically fall in the 70-99 range), the following three are a sequence number, and the last digit is a calculated checksum. This tool validates the checksum only — it doesn't decode or verify the date or region.
Does a valid checksum mean the JMBG belongs to a real, registered person?
No. It only confirms the 13 digits are mathematically self-consistent. Confirming a JMBG is genuinely issued requires access to Serbia's population register, which this tool doesn't query.