Interest Rate Comparison Calculator
Compare two interest rates on the same loan to see how much the monthly payment and total interest change.
Compare Your Options And Get Clear Answers
Compare two interest rates on the same loan to see how much the monthly payment and total interest change.
Interest Rate Comparison Estimator
Enter your numbers below for an instant estimate.
How It Works
Key concepts behind this calculator
Monthly Payment
Standard repayment formula using each rate.
Total Repaid
Monthly payment multiplied by the number of months.
Compare
Total repaid minus the loan shows the total interest for each rate.
Use As A Guide
Results are estimates based on your inputs. Check real quotes, rates and professional advice before deciding.
Rate Impact Examples
Monthly payment on £200,000 over 25 years.
| Rate | Monthly Payment | Total Interest | Total Repaid |
|---|---|---|---|
| 3.5% | £1,001 | £100,300 | £300,300 |
| 4.5% | £1,112 | £133,600 | £333,600 |
| 5.5% | £1,228 | £168,400 | £368,400 |
| 6.5% | £1,350 | £205,000 | £405,000 |
| Rule of Thumb | 1% ≈ £120 a month here | Compare APR | Rates change often |
Interest Rate Comparison Calculator FAQ
Answers to common questions about this calculator.
On a long loan a 1 percentage point difference can change the monthly payment by around 10% and total interest by tens of thousands.
The annual percentage rate includes interest plus most fees, so it is better for comparing offers.
Yes, for any fixed-rate repayment loan.
No. It is a calculator for general comparison only.