How is the Kazakh BIN/IIN check digit calculated?

Multiply the first 11 digits by the weights 1 through 11 and take the sum modulo 11. If the result is 10, recompute with the shifted weights 3,4,5,6,7,8,9,10,11,1,2. The 12th digit must equal that control digit.

What is the difference between a BIN and an IIN?

A BIN (business identification number) identifies a legal entity, while an IIN (individual identification number) identifies a person. Both are 12 digits and use the same check-digit algorithm; the 5th digit distinguishes them.

What does the tool decode from an IIN?

An IIN encodes the holder's birth date in its first six digits and a century/sex marker in the seventh digit, so the tool shows the inferred birth date and sex when the structure is recognised.

What if the checksum equals 10 under both weight sets?

A control digit of 10 cannot be represented in one position, so a code whose checksum resolves to 10 under both the primary and shifted weights is invalid and is rejected.

Is my BIN/IIN sent anywhere?

No. The check runs entirely in your browser, so the code never leaves your device and nothing is logged or transmitted.

Kazakhstan BIN/IIN Validator

The BIN (business identification number) and IIN (individual identification number) are Kazakhstan’s 12-digit identifiers for companies and people. They appear on contracts, tax records and SNT e-invoicing submissions. Both share a modulo-11 check digit, so a single mistyped digit is detectable. This free validator runs the exact algorithm in your browser and decodes the encoded structure.

How it works

The official check-digit algorithm operates on the first 11 digits:

Multiply each of the first 11 digits by the weights 1,2,3,4,5,6,7,8,9,10,11 and sum.
Take control = sum mod 11.
If control equals 10, recompute with the shifted weights 3,4,5,6,7,8,9,10,11,1,2. If that result is also 10, the code is invalid.
The 12th digit must equal the control digit.

The structure also carries meaning. In an IIN, the first six digits are the birth date YYMMDD, and the seventh digit is a century/sex marker: 1/2 for the 1900s, 3/4 for the 2000s, 5/6 for the 2100s, with odd values male and even female. In a BIN, the fifth digit marks the registration type (4 resident legal entity, 5 non-resident, 6 branch).

Example

For an IIN beginning 940825... the tool decodes a 1994-08-25 birth date once the century marker is read from the seventh digit, then verifies the 12th digit against the modulo-11 control digit. A matching control digit means the code is valid.

A valid check digit confirms the code is well-formed, not that the person or company is registered. The decoded details are inferred from the structure. All processing stays on your device.