Estimate your monthly loan repayment, total interest charged and total cost of borrowing. Works for personal loans, car finance, consolidation loans and any fixed-term credit. Enter the loan amount, interest rate and term below.
Enter the loan amount you want to borrow, the annual interest rate quoted by the lender, and the repayment term in months. The calculator uses the amortisation formula to produce the equal monthly payment that clears the loan with interest by the final month.
Monthly Payment — what you pay each month throughout the term.
Total Interest — the full cost of borrowing on top of the loan amount.
Total Cost — what you pay back in total (loan plus all interest).
Try increasing and decreasing the term to see the trade-off between lower monthly payments and higher total interest.
Loan £8,000 at 9% APR over 48 months → monthly payment approximately £199, total interest approximately £1,552, total repaid £9,552.
A loan calculator helps you understand the true cost of borrowing before you commit. The two figures most people focus on when taking a loan are the monthly payment and the total amount repaid — but they are often in tension with each other. Extending the term reduces the monthly payment but increases the total interest paid significantly. This tool makes that trade-off visible before you sign anything.
All standard fixed-rate personal loans use the amortisation formula, which front-loads interest payments. In the early months of a loan, most of your payment is interest; in the later months, most is capital repayment. The total interest figure shown by this calculator accounts for this structure.
Use the APR figure from a lender's quote, not just the advertised interest rate. Some lenders quote a flat interest rate that is lower than the APR — but the APR is the true cost comparison figure. The APR includes any mandatory arrangement fees spread over the loan term.
Run several scenarios: compare 24 months versus 36 months versus 48 months for the same loan amount and rate. Print or note the results side by side to see the difference in total interest for each term. For many people, the middle option offers the best balance of manageable monthly payment and reasonable total cost.
Before taking any consumer credit, the FCA-regulated resources at moneyhelper.org.uk provide free impartial guidance on loans, credit and debt. If you are consolidating existing debt, Citizens Advice offers free guidance on whether consolidation is genuinely beneficial in your situation.
If you are struggling with existing debts, StepChange Debt Charity (stepchange.org) offers free debt advice and structured repayment plans — including debt management plans that can reduce monthly payments and freeze interest in appropriate cases.
Common questions about this calculator and how to use it.