Loan & Mortgage Calculator — monthly payment, free
Calculate the monthly payment, total interest and payoff total for a loan or mortgage from the amount, rate and term. Free, with a full amortisation view.
About the Loan calculator tool
The monthly payment is the number lenders lead with, and on its own it tells you remarkably little. Two loans with the same monthly figure can differ by tens of thousands over their lifetimes, because a longer term spreads a smaller payment across far more months and collects interest for every one of them. Seeing the payment, the total interest and the total repaid together is what turns an affordable-sounding offer into a decision you can actually evaluate.
Amortisation is the mechanism behind the shape of a loan, and it is worth understanding because it is counterintuitive. Each payment is split between interest on the balance outstanding and repayment of the balance itself. Early on the balance is large, so most of the payment is interest and very little of the debt goes away. As the balance falls the split shifts, and by the final years almost all of each payment reduces the principal. This is why paying a mortgage for five years can leave the balance barely moved.
It also explains why overpayments are so effective, and why they are most effective early. Money paid above the required amount goes straight against the principal, and every unit of principal removed cancels all the interest that would have accrued on it for the entire remaining term. A modest overpayment in the first years of a long mortgage can shorten it by a surprising margin — far more than the same amount paid near the end.
What this calculation covers is the loan itself: principal, interest and term. A real mortgage or car loan carries costs it does not model — arrangement and origination fees, property insurance, taxes, mortgage insurance where the deposit is small, and early repayment charges. Those can add substantially to the true monthly outlay, so treat the figure here as the cost of borrowing the money rather than the full cost of the purchase.
How it works
Enter the loan
Put in the amount borrowed, the annual interest rate and the term in years.
See the real cost
The monthly payment appears alongside the total interest and the total amount repaid over the full term.
Compare scenarios
Change the term or rate and watch the totals move. A shorter term costs more monthly and far less overall.
Frequently asked questions
- How is the monthly payment calculated?
- With the standard amortisation formula, which finds the fixed payment that clears the balance exactly over the term while covering interest on the declining balance each month. The annual rate is divided by twelve and the term converted to months. It is the same calculation banks use, so the figure should match a lender's quote for the same three inputs.
- Why is so much of my early payment interest?
- Because interest is charged on the balance outstanding, and at the start that balance is at its maximum. Only what is left after covering interest reduces the debt. As the balance falls the interest portion shrinks and repayment accelerates, which is why progress feels glacial for years and then noticeably quickens toward the end of the term.
- Should I choose a shorter or longer term?
- A shorter term costs more each month and dramatically less overall, because interest accrues for fewer years. A longer term buys affordability at a real price — often tens of thousands more in total. The sensible approach is the shortest term whose payment you can meet comfortably even if your circumstances tighten, rather than the shortest you can theoretically afford.
- How much do overpayments actually save?
- More than most people expect, especially early. Overpayment goes entirely against the principal, cancelling every unit of interest that principal would have generated across the whole remaining term. On a long mortgage, a consistent modest overpayment from the start can remove several years and a large sum in interest. Check for early repayment charges first.
- Does this include fees, insurance and taxes?
- No. It calculates the cost of the borrowing itself — principal, interest and term. Real loans add arrangement or origination fees, property taxes, buildings insurance, and mortgage insurance where the deposit is below a threshold. Those can raise the actual monthly outlay considerably, so budget from a lender's full illustration rather than from this figure alone.
- What is the difference between the interest rate and the APR?
- The interest rate is what is charged on the balance. The APR folds in mandatory fees and charges to express the total cost as a single annual percentage, which makes it the fairer number for comparing offers. A loan with a low headline rate and heavy fees can carry a higher APR than one that looks more expensive.
- Is my financial information sent anywhere?
- No. The calculation runs in your browser tab and nothing is transmitted, stored or logged — no amounts, no rates, no results. Nobody sees what you are considering borrowing, which is not something you can take for granted on a comparison site whose business model is passing enquiries to lenders.