The calculation method for credit card overdue fees is as follows:

1. First, the overdue fees are calculated based on the number of overdue days and the overdue amount.

2. Specifically, the longer the overdue period, the higher the overdue handling fee. Usually, banks will set different levels of overdue days and corresponding different handling rates.

3. Overdue amount refers to the amount of debt that has not been repaid on time. Banks usually divide overdue amounts into several ranges and set different handling rates for each range.

4. The possible situation is that if the overdue days are short and the overdue amount is small, the handling fee may only be a certain proportion of the overdue amount; and if the overdue days are long and the overdue amount is large, the handling fee may be Compound calculations will be made based on the overdue amount and overdue days.

5. Summary: The calculation of credit card overdue fees is determined based on the number of overdue days and overdue amount. The specific rate is determined according to the bank's regulations.

Extended information (for reference only): The specific calculation method of credit card overdue fees may vary from bank to bank, and the information provided here is only a general overview. It is recommended that cardholders should keep abreast of the relevant regulations of their bank when using credit cards, and ensure repayment on time to avoid additional overdue fees. If you have any questions or need specific calculations, please consult the customer service of the card-issuing bank or read the relevant terms.