Loan Repayment Calculator

Monthly repayments and total interest for personal, car or any fixed-rate loan.

Loan repayment
Monthly payment
Total repaid
Total interest
Personal loan calculator
Works for car loans, personal loans, and any fixed-rate instalment loan. The same formula as a mortgage — just typically over a shorter term.
M = P · r(1+r)ⁿ / [(1+r)ⁿ − 1]
1
Shorter term → higher monthly payments, but far less interest overall
2
Lower interest rate → dramatically lower total cost
💡 Tip: Even dropping your rate by 0.5% can save hundreds over the life of a personal loan. Always compare APR, not just the headline rate.

Working out the true cost of a loan

Whether it is a car, a personal loan, or debt consolidation, the advertised monthly repayment rarely tells the whole story. This calculator reveals the monthly repayment, the total you will repay over the life of the loan, and the total interest — the extra you pay for the privilege of borrowing.

How to use the loan calculator

Enter the loan amount, the annual interest rate, and the term in years. Personal and car loans typically run over one to seven years. Shortening the term raises the monthly payment but cuts the total interest sharply, so it is worth testing a few combinations.

How the numbers work

Loans use the same amortisation formula as a mortgage: M = P · r(1+r)n / [(1+r)n − 1]. Each payment covers the interest accrued that month first, and whatever remains reduces the balance. Because the balance is highest at the start, early payments are interest-heavy.

Compare the APR, not the headline rate

Two loans with the same interest rate can cost very different amounts once fees are included, which is why the APR (annual percentage rate) is the fairer comparison — it folds fees into a single figure. Even a 0.5% difference in rate can save hundreds over a few years. If you can make extra repayments without penalty, doing so early in the term saves the most, because you cut the balance while it is still large.

Frequently asked questions

How are loan repayments worked out?

The same amortisation formula as a mortgage: M = P × r(1+r)^n / [(1+r)^n − 1], usually over a shorter term. P is the loan, r the monthly rate, n the number of payments.

Should I compare interest rate or APR?

Compare the APR (annual percentage rate) where possible, because it includes fees. A lower headline rate with high fees can cost more than a slightly higher APR.