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Loan repayment and interest calculator

Find your monthly repayment and the real cost of a loan, in any currency. Works for flat rate and reducing balance loans.

Updated October 2026

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Not sure? Many loan apps and cooperatives use flat rates. Banks usually use reducing balance. Check your loan terms.
Add upfront fees
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Fees taken from the loan when it is paid out. You repay the full amount but receive less, which raises the true cost.

Flat rate vs reducing balance

With a reducing balance loan, interest is charged only on what you still owe, so it shrinks as you repay. With a flat rate, interest is charged on the original amount for the whole term, even though you repay it month by month.

That is why a flat rate costs much more than it looks. A 24% flat loan over 12 months works out to roughly 42% a year on a reducing balance. The "true cost" figure above shows this for your loan.

Common questions

What does the true cost (APR) mean?

It is the yearly rate you really pay once the way interest is charged and any upfront fees are counted. It lets you compare loans fairly, even when they quote rates in different ways.

My lender quotes a monthly rate. What do I do?

Choose "per month" next to the rate. A rate of 3% a month is not 3% a year, so the monthly option matters a lot.

Does this include late fees or insurance?

Only upfront fees you enter. Late payment charges, ongoing insurance and other costs in your loan agreement are not included, so read the terms carefully.

How can I check a lender is genuine?

Check that the lender is licensed by your country's financial regulator before you borrow. Be wary of lenders who ask for access to your contacts or photos, or who ask for payment before they pay out the loan.

More calculators

Estimates only. These calculators give a guide and are not financial, tax or legal advice. Tax figures use the Nigeria Tax Act 2025 rates effective January 2026. Loan and savings results depend on your lender's or provider's exact terms. Check details with the lender, your employer, a qualified adviser or the relevant authority before you decide.