How is the clé RIB calculated?

Letters in the account number become digits (A and J = 1, B, K and S = 2 …), then key = 97 − ((89 × bank + 15 × branch + 3 × account) mod 97).

Yes: a French or Monaco IBAN contains the RIB, which is split out and checked.

Does a valid check digit mean the number exists?

No — only that it is correctly written. Whether it was issued, and to whom, only the issuing authority can say. The checker never makes up numbers either: it checks the ones you type.

Is anything uploaded?

No. The check is worked out in your browser, and nothing you type leaves your computer.

RIB key calculator

The clé RIB, worked out.

Examples temporarily replace the input and settings. You can restore your previous work.

Input0 characters

Output

Paste or type above to see the result here.

Your files stay on your device

This tool runs entirely in your browser. What you paste is processed on your device and is never sent to a server, so it is safe to use with tokens, keys and unpublished text.

Example

Worked example — RIB key calculator

Use the following inputs and settings. Keep other settings at the page defaults.

Item	Value
Input	20041 01005 0500013M026 06
kind	rib
Output	✓ 20041 01005 0500013M026 06 — valid RIB
Output	banque 20041 · guichet 01005 · compte 0500013M026 · clé 06
Output	Letters to digits: M → 4 → 20041 01005 05000134026
Output	89 × 20041 + 15 × 01005 + 3 × 05000134026 = 15002200802
Output	15002200802 mod 97 = 91 → 97 − 91 = 06 ✓
Output	A correct check digit only means the number is well-formed; it doesn’t mean the number exists or belongs to anyone. Nothing is sent anywhere: the check runs in your browser.

Expected result — ✓ 20041 01005 0500013M026 06 — valid RIB

How it works

Paste one number a line; dots, dashes and spaces are fine.
Each is checked for its length and its check digits.
The result shows each step of the calculation, and where a number fails.

Frequently asked questions

How is the clé RIB calculated?: Letters in the account number become digits (A and J = 1, B, K and S = 2 …), then key = 97 − ((89 × bank + 15 × branch + 3 × account) mod 97).
Can I paste an IBAN?: Yes: a French or Monaco IBAN contains the RIB, which is split out and checked.
Does a valid check digit mean the number exists?: No — only that it is correctly written. Whether it was issued, and to whom, only the issuing authority can say. The checker never makes up numbers either: it checks the ones you type.
Is anything uploaded?: No. The check is worked out in your browser, and nothing you type leaves your computer.