Mortgage Calculator

What does the monthly figure include?

Principal and interest only. It does not include property tax, homeowners insurance, private mortgage insurance, HOA dues or closing costs. Those are usually collected alongside the mortgage in an escrow payment, which is why the number your lender quotes is normally larger than the one here — sometimes by several hundred a month.

What formula does it use?

The standard fixed-rate amortisation formula: M = P × r(1+r)^n / ((1+r)^n − 1), where P is the amount borrowed, r is the annual rate divided by 12, and n is the term in months. The amount borrowed is the home price minus your down payment.

Why does the total interest look so large?

Because interest is charged on the outstanding balance every month for the whole term, and early on the balance is nearly the full loan. On a long fixed-rate mortgage the interest can approach or exceed the amount borrowed. Try shortening the term in the calculator and watch the total drop — that comparison is the most useful thing this tool does.

Why do the early payments barely reduce what I owe?

Every payment is the same size, but its split is not. At the start, most of it covers the interest accrued that month and only a sliver touches the principal; as the balance falls the interest shrinks and the principal share grows. This is why paying a little extra in the first years removes far more total interest than the same amount paid near the end.

Does it model an adjustable rate, or extra payments?

No. It assumes one fixed rate for the entire term and equal payments throughout. An adjustable-rate mortgage, an offset account, a payment holiday or overpayments all change the schedule in ways this calculator does not attempt to represent.

Will the rate I enter be the rate I get?

Not necessarily. Advertised rates typically assume a strong credit profile and a particular loan-to-value ratio. Your actual offer depends on credit history, deposit size, property type and the lender's own pricing. Use a rate range rather than a single optimistic figure when comparing scenarios.

Is anything I type sent anywhere?

No. The amortisation runs in your browser; no figures are transmitted or stored.

Can I decide what house I can afford from this?

No. This is arithmetic on numbers you supplied, not affordability advice. What you can safely borrow depends on your income stability, other debts, deposit, and the running costs of the property. Talk to a mortgage broker or a qualified adviser before committing.