MONEY & BUSINESS / HOME LOANS

Mortgage calculator

Work out your monthly mortgage payment, the total interest, and how much time and interest a regular overpayment saves.

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Your numbers

Optional. Extra paid each month on top of the normal payment.
This labels amounts; it does not convert between currencies.
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YOUR RESULT

Enter your numbers to see a result.

WORKED EXAMPLE

Mortgage calculator: a worked example

With property price 300,000, deposit (%) 10, interest rate (%) 4.5, mortgage term (years) 25, monthly overpayment 0, the monthly mortgage payment is $1,500.75.

Inputs
Property price300,000
Deposit (%)10
Interest rate (%)4.5
Mortgage term (years)25
Monthly overpayment0
Results
Monthly mortgage payment$1,500.75
Loan amount$270,000.00
Total interest over the term$180,224.31
Interest saved by overpaying$0.00
Time saved by overpaying0 years
Mortgage paid off after25 years

Amounts are shown in US dollars for illustration. Choose your own currency in the calculator above; it labels amounts and does not convert them.

THE METHOD

How it works

Enter the property price, your deposit, the interest rate and the term. A repayment mortgage pays off interest and capital each month, so early payments are mostly interest. An overpayment goes straight to the balance, which cuts the interest charged in every later month and shortens the term.

FormulaMonthly payment = L × r ÷ (1 − (1 + r)^−n), where L = price − deposit, r = annual rate ÷ 12 ÷ 100 and n = months.
ASSUMPTIONS

Assumptions and limits

  • A repayment mortgage at a fixed rate, paid monthly, for the whole term.
  • Arrangement fees, insurance, rate changes at the end of a fixed period and early-repayment charges are not included.
  • Overpayments are assumed to reduce the balance immediately each month. Many lenders cap penalty-free overpayments each year.
  • Results are estimates based on the inputs and assumptions on this page, not professional advice.
  • Try this: in the example above, a 10% rise in “Property price” changes the result by +10.0% and a 12% rise in “Mortgage term (years)” changes the result by -5.7%. Use “Save scenario A”, change one input and compare the two results side by side.
QUESTIONS

Frequently asked questions

How is the result of the “Mortgage calculator” calculated?

Monthly payment = L × r ÷ (1 − (1 + r)^−n), where L = price − deposit, r = annual rate ÷ 12 ÷ 100 and n = months. Enter the property price, your deposit, the interest rate and the term. A repayment mortgage pays off interest and capital each month, so early payments are mostly interest. An overpayment goes straight to the balance, which cuts the interest charged in every later month and shortens the term.

What does the worked example show?

With property price 300,000, deposit (%) 10, interest rate (%) 4.5, mortgage term (years) 25, monthly overpayment 0, the monthly mortgage payment is $1,500.75. Loan amount: $270,000.00; Total interest over the term: $180,224.31; Interest saved by overpaying: $0.00; Time saved by overpaying: 0 years; Mortgage paid off after: 25 years.

What assumptions and limits apply?

This is an estimate based on the inputs and assumptions shown on this page, not professional advice. Check anything with financial, health or safety consequences independently.

Is my data private?

Yes. Calculations run in your browser and your numbers are not sent to a server. A share link contains the inputs you choose to share, so check it before sending it to anyone.

Can I use my own currency?

Yes. Pick from 33 currencies and the amounts are labelled to match. The selector does not convert between currencies, so enter prices in your own currency.

How much does an overpayment save?

The calculator compares your mortgage with and without the extra monthly amount. Because each overpayment reduces the balance that interest is charged on, the interest saved is usually much larger than the overpayments themselves, and the mortgage ends earlier.

Does this work for interest-only mortgages?

No. It models a repayment mortgage, where each payment covers interest and repays part of the loan.

FOR WEBSITE OWNERS

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Free to use. Paste this where you want the calculator to appear. It resizes itself and links back to Calculator786. Optional: add data-currency="EUR" to the div to preset a currency.