InstalmentLoans

Total Cost of Credit Calculator

A total cost of credit calculator adds up everything you repay on top of the amount you borrow. Enter the amount, representative APR, term and any arrangement fee to see the monthly repayment, the interest and the full cost of the loan.

By the InstalmentLoans Editorial Team · Last updated 2 October 2026

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Enter your numbers and press Calculate. Nothing you type leaves your browser.

How this calculator works

The total cost of credit is the amount you repay minus the amount you borrowed. It covers interest and any arrangement fee, but not optional extras.

Amount financed = amount borrowed + arrangement fee.

Monthly repayment M = financed * r * (1 + r)^n / ((1 + r)^n - 1), where r is the annual rate / 12 / 100 and n is the term in months.

Total cost of credit = (M * n) - amount borrowed.

A fee raises the amount financed, so it increases both the repayment and the total cost of credit. Enter your own rate and fee from a real offer.

Frequently asked questions

What exactly is the total cost of credit?
It is everything you repay above the cash you receive: the interest charged over the term plus any arrangement fee set by the lender.
How does an arrangement fee change the cost?
The fee is added to the amount financed, so you pay interest on it as well as repaying it. That raises the monthly repayment and the total cost of credit.
Is the total cost of credit the same as the APR?
No. The total cost of credit is a cash amount over the life of the loan. The APR is an annual percentage that also reflects fees, which makes it useful for comparing loans of different sizes and terms.
Why is my total cost higher than the interest I expected?
Longer terms and higher rates both add to the cost. Because interest is charged on the balance each month, a loan repaid over more months usually costs more overall.

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