calcfig
USUKAU

Mortgage Calculator (Monthly Payment)

Work out the monthly principal and interest payment on a mortgage from the loan amount, rate and term, see the total interest, and test what an extra payment each month saves.

$

The amount you borrow, not the price of the home.

% a year

A placeholder, not a quote. Use the rate from your lender.

years
$

Paid off the loan today, for example from savings or a bonus.

$

Added to every repayment. It shows the interest and time saved.

$

Account or package fees. Added to the total cost, not to the loan.

Monthly repayment$1,896.20
Total interest$382,633.47
Total repaid$682,633.47

$300,000.00 at 6.5% a year is 0.5417% a month (rate ÷ 12) over 360 payments. Payment = loan × r ÷ (1 − (1 + r)^−n) = $1,896.20. 360 × $1,896.20 = $682,633.47 repaid, less the $300,000.00 borrowed = $382,633.47 interest.

Principal and interest only. Property tax, homeowners insurance, mortgage insurance and HOA fees are not included. Check the figure with your lender.

Fig. 1 Your repayment, and what the loan costs.

Every formula is tested against worked examples. How we check

TermMonthly repaymentTotal interest
15 years$2,613.32$170,397.98
20 years$2,236.72$236,812.66
25 years$2,025.62$307,686.45
30 years$1,896.20$382,633.47

Fig. 2 The same loan and rate over different terms.

Last checked 11/11/2026. Sources: CFPB: What is the difference between my principal and interest payment and my total monthly payment?.

Guide

How the repayment is worked out

Interest is charged each month at the yearly rate divided by 12. The level repayment that clears the loan over n payments is loan × r ÷ (1 − (1 + r)−n), where r is the rate for one period.

For example, $300,000.00 at 6.5% over 30 years is $1,896.20 a month. That is 360 payments, $682,633.47 in all, so $382,633.47 of it is interest. The rate, term and loan amount here are placeholders, not a quote.

What is not included

This is the principal and interest payment only. Your total monthly payment can also include homeowners insurance, property taxes and possibly mortgage insurance, often collected through an escrow account, and condo or HOA fees are usually paid separately (CFPB, linked below). When you compare lenders, compare the principal and interest figure.

Extra repayments

Anything you pay above the payment goes towards the amount you owe, so less interest is charged from then on. An extra $200 a month on the example above pays the loan off in 23 years 1 month instead of 30 years, and saves $103,448.79 of interest. Put an amount in the extra box to try your own.

Some lenders limit or charge for extra repayments on fixed-rate loans, so ask yours.

A one-off payment

A one-off payment now reduces the amount you owe straight away. On the example, paying $10,000.00 on day one pays the loan off in 27 years 3 months and saves $53,916.69 of interest. You can use the one-off box, the extra box and the offset box together.

Term and rate

A longer term lowers the payment but costs more interest, which the comparison table shows. A higher rate costs more too: on the example, 7.5% instead of 6.5% makes the payment $2,097.64 a month.

Common questions

Does this include property tax and insurance?

No. It is the principal and interest payment only. Your lender can tell you the property tax, insurance and any mortgage insurance in your total monthly payment.

How much does an extra payment save?

On $300,000.00 at 6.5% over 30 years, an extra $200 a month saves $103,448.79 of interest and shortens the loan by 6 years 11 months. Your own numbers will differ, so enter them.

Why is so much of the early payment interest?

Interest is charged on the whole balance. In the first month of the example, $300,000.00 at 6.5% a year is $1,625.00 of interest, so only $271.20 of the $1,896.20 reduces the loan. The share that reduces the loan grows each month.

Is the interest rate fixed?

This assumes the same rate for the whole term. If your rate is variable or a fixed period ends, run it again with the new rate, the balance owing and the years left.

What next?