Loan amount, APR and term → your monthly payment, total interest, and how the balance falls each year.
Amortisation summary
| Year | Interest paid | Principal paid | Balance left |
|---|
Assumes a fixed rate for the whole term, equal monthly payments, and interest charged monthly on the outstanding balance.
About this calculator
This uses the standard amortising loan formula: your monthly payment is fixed for the whole term, and each payment covers the interest charged that month first, with whatever's left reducing the balance. Because the balance falls over time, the interest portion shrinks each month and the principal portion grows — which is why the early payments on a loan barely dent the amount you owe.
The amortisation summary shows that split year by year: how much of the year's payments went on interest, how much came off the balance, and what's still outstanding at the end of each year.
APR is treated here as a nominal annual rate divided into twelve monthly periods, which is how most loan repayment schedules are built. A lender's advertised APR may also fold in compulsory fees, so a quote based on the same headline rate can differ slightly from this estimate.
This is a planning estimate rather than a formal quote or financial advice — always check the actual figures in a lender's illustration before committing.
Frequently asked questions
What is the difference between APR and the interest rate?
The interest rate covers only the cost of borrowing, while APR is meant to include compulsory fees as well, giving a fuller cost of the loan. This calculator applies the figure you enter as the annual rate spread across monthly payments.
Why does so little of my early payments come off the balance?
Interest is charged on whatever you still owe, and early on that balance is at its largest. Your payment is fixed, so most of it goes on interest at first and the principal share grows steadily as the balance falls.
Does a longer loan term cost more overall?
Usually yes. Spreading the same loan over more months lowers each payment but leaves the balance outstanding for longer, so you pay interest for more months and the total repaid rises.