International · Validation
RF creditor reference generator.
Generate an ISO 11649 RF creditor reference from your own invoice or customer number, or check an existing one. Everything runs in your browser: nothing you type is transmitted anywhere.
Inputs
Result
Generate a reference, or enter an RF number to validate.
How the RF creditor reference check digits work
A Creditor Reference is defined by ISO 11649. It is the letters RF, two check digits, then a reference of 1 to 21 letters and digits, so 5 to 25 characters in all. It is printed in blocks of four characters (RF18 5390 0754 7034), as in the Swiss QR-bill guidelines.
Generating
- Append
RF00to the end of your reference. - Replace each letter with a number (A=10 … Z=35) and read the result as one large integer.
- Take it mod 97 and compute
98 − remainder. Pad to two digits. Those are the check digits.
Validating
Move the first four characters (RF and the check digits) to the end, convert letters to numbers, and take the result mod 97. The reference is consistent if the remainder is exactly 1 (ISO 7064 MOD 97-10, the same rule an IBAN uses). Leading zeros in the reference do not change the check digits.
Verification
The reference 539007547034 gives check digits 18, i.e. RF18 5390 0754 7034, the example used by both python-stdnum and Wikipedia. Altered check digits or body characters fail.
Sources
python-stdnum — stdnum/iso11649.py; Wikipedia — Creditor Reference; SIX — Swiss QR-bill Implementation Guidelines, ch. 3.6.2.
What a passing checksum does and doesn’t tell you
This tool checks format and checksum only. A valid remainder proves the characters are internally consistent — it cannot confirm the reference was issued or belongs to anyone, and a generated reference is not registered with any bank. Your bank or biller decides which references it accepts. This tool runs entirely in your browser: nothing you type is transmitted, stored, or logged.