UK Take-Home Pay Calculator
A take home pay calculator shows what lands in your bank after income tax, National Insurance, pension and…
Mortgage Calculator
A mortgage calculator estimates your monthly repayment from the property price, your deposit, the interest rate and the term. Borrowing $320,000 at 6.5% over 30 years costs $2,022.62 a month and $408,142 in interest. Add an overpayment to see how much sooner you could be mortgage-free.
How to use this mortgage repayment calculator
- Enter the price. Type the purchase price of the home, not the amount you want to borrow.
- Add your deposit. Enter the cash you are putting down. The tool subtracts it to find the loan amount and your loan-to-value (LTV).
- Set the rate and term. Use the annual rate from your quote and pick the term. Fixed-rate deals in the UK and Europe usually last 2–10 years, so re-run the numbers for the rate you expect afterwards.
- Try an overpayment. Add a monthly overpayment to see the new payoff date and the interest you would save.
- Read the schedule. Open the yearly table to see how much of each year’s payments clears the balance and how much goes to interest.
What a monthly mortgage payment calculator actually works out
Every repayment mortgage payment has two parts. Interest is charged on whatever you still owe, and the rest of the payment, the principal, reduces that balance. Because the balance is largest at the start, early payments are mostly interest. On a $320,000 loan at 6.5%, the first payment of $2,022.62 is split into $1,733.33 of interest and only $289.28 of principal.
The payment itself stays flat for as long as the rate is fixed. What changes month to month is the split: a little more goes to principal each time, which is why the balance falls slowly at first and quickly near the end.
A US lender often quotes PITI (principal, interest, tax and insurance). Use the optional costs box for the tax and insurance part so your total matches the quote.
The mortgage payment formula
The standard formula for a fixed-rate repayment loan is:
M = P × r × (1 + r)n ÷ ((1 + r)n − 1)
- M is the monthly payment
- P is the amount borrowed (price minus deposit)
- r is the monthly rate: the annual rate ÷ 12 ÷ 100
- n is the number of payments: years × 12
Worked example: P = $320,000, annual rate 6.5% so r = 0.0054167, and n = 360. That gives M = $2,022.62. Over 360 payments you repay $728,142, of which $408,142 is interest.
How rate and term change the total cost
The table below keeps the loan at $320,000 and changes one thing at a time. A shorter term raises the payment but cuts total interest sharply; a single percentage point on the rate moves the lifetime cost by roughly $75,000.
| Rate | Term | Monthly payment | Total interest |
|---|---|---|---|
| 6.5% | 15 years | $2,787.54 | $181,758 |
| 6.5% | 25 years | $2,160.66 | $328,199 |
| 6.5% | 30 years | $2,022.62 | $408,142 |
| 5.5% | 30 years | $1,816.92 | $334,093 |
| 7.5% | 30 years | $2,237.49 | $485,495 |
Why the size of your deposit matters
A bigger deposit lowers the loan, and it often lowers the rate too, because lenders price risk by loan-to-value. Holding the rate at 6.5% over 30 years on a $400,000 home:
| Deposit | LTV | Loan | Monthly payment |
|---|---|---|---|
| $20,000 (5%) | 95% | $380,000 | $2,401.86 |
| $40,000 (10%) | 90% | $360,000 | $2,275.44 |
| $80,000 (20%) | 80% | $320,000 | $2,022.62 |
| $120,000 (30%) | 70% | $280,000 | $1,769.79 |
In practice the 90–95% LTV rows would usually carry a higher rate, and in the US a conventional loan above 80% LTV normally adds private mortgage insurance until you reach 20% equity.
Using it as a mortgage overpayment calculator
Extra money paid on top of the required repayment goes straight to principal, so it stops interest building on that amount for the rest of the loan. Adding $200 a month to the $320,000, 6.5%, 30-year example pays the loan off in 23 years 5 months instead of 30 years and saves about $105,429 in interest.
Before you overpay, check two things. Many UK and European fixed-rate deals allow only around 10% of the balance per year without an early repayment charge. And if you carry expensive debt, such as a credit card, paying that off first usually saves more.
Reading your mortgage amortization schedule
The yearly table under your result is an amortization schedule. Each row shows how much principal and interest you paid that year and the balance left at the end. Watch for the crossover year when principal paid overtakes interest paid; on the 6.5%, 30-year example it arrives in year 20. That point is useful if you are deciding when to remortgage or whether overpaying early is worth it.
US and UK mortgages: the same maths, different words
- Down payment vs deposit: the same thing. US buyers say down payment; UK and Irish buyers say deposit.
- Term: 30 years is the US norm with the rate fixed for the full term. In the UK, 25 years is common, rates are usually fixed for 2 or 5 years, and then move to the lender’s standard variable rate unless you remortgage.
- Insurance: US conventional loans above 80% LTV usually need PMI. UK lenders price the higher risk into the rate instead.
- Affordability: UK lenders typically cap borrowing at around 4–4.5 times income; US lenders look at debt-to-income ratios.
Whichever market you are in, the payment formula above is identical; only the inputs change.
Mortgage calculator FAQs
How much is the monthly payment on a $300,000 mortgage?
At 6.5% over 30 years, a $300,000 mortgage costs about $1,896 a month before tax and insurance. Over 25 years it rises to about $2,026, and over 15 years to about $2,613.
Does this mortgage calculator include property tax and insurance?
Only if you add them. Enter your monthly property tax, homeowners insurance, HOA dues or PMI in the optional costs box and the result shows the loan payment and the full monthly total separately.
Is it better to choose a 15-year or 30-year mortgage?
A 15-year term has a higher payment but far lower total interest, and the rate is often lower too. A 30-year term keeps the payment affordable and leaves room to overpay when you can. Many borrowers take the longer term and overpay voluntarily.
Can I use this for an interest-only mortgage?
No. This tool calculates repayment (capital and interest) mortgages. On an interest-only loan your monthly payment is simply the balance × annual rate ÷ 12, and the full balance is still owed at the end.
How accurate is the result?
The repayment uses the same formula lenders use, so for a fixed rate it matches to the cent. Real costs can differ because of fees, rate changes after a fixed period, and how your lender rounds.
Sources and methodology
Payments use the standard annuity formula with monthly compounding. The schedule is computed month by month and summarised by year. Overpayments are applied to principal in the month they are paid. Figures in the tables above were calculated with this tool and rounded to the nearest cent or dollar.
- Consumer Financial Protection Bureau: Owning a Home — US loan costs, PMI and closing costs
- MoneyHelper: Mortgages — UK government-backed guidance on mortgage types and overpayments
- Freddie Mac Primary Mortgage Market Survey — Weekly average US mortgage rates
- Bank of England: Mortgage lending statistics — UK lending data
Figures and thresholds valid for rates and rules as of October 2026.
Related calculators
US Paycheck Calculator
A paycheck calculator estimates take-home pay after federal income tax, Social Security, Medicare and pre-tax deductions. On a…
Compound Interest Calculator
A compound interest calculator shows how money grows when interest earns interest. $10,000 at 5% compounded monthly becomes…
Loan Calculator
A loan calculator shows the fixed monthly payment on an amortizing loan and how much interest you pay…