Loan & Mortgage Calculator
Work out monthly repayments, total interest and a payoff schedule.
Yearly payoff schedule
| Year | Principal paid | Interest paid | Balance |
|---|
Estimates only. Excludes taxes, insurance, fees and any introductory rates.
How loan repayments are calculated
A fixed-rate loan is repaid in equal monthly instalments. Each payment covers the interest due that month, and the rest reduces the balance — so early payments are mostly interest and later payments are mostly principal.
M = P × r (1 + r)n ÷ ((1 + r)n − 1)
| M | Monthly payment |
|---|---|
| P | Amount borrowed |
| r | Monthly interest rate (annual ÷ 12) |
| n | Total number of payments (years × 12) |
Paying a little extra each month, or making one extra payment a year, can shorten the term and cut total interest substantially because the balance — and the interest charged on it — falls faster.
A $300,000 mortgage at 6% over 30 years works out to about $1,799 a month. Across the full term you would repay roughly $647,515 in total, of which around $347,515 is interest.
The real cost of how long you borrow
Stretching a loan over more years lowers each monthly payment but increases the total interest you pay, sometimes dramatically. A shorter term does the opposite: higher payments, far less interest overall. It is worth comparing a few terms side by side before committing.
Ways to pay less interest
- Overpay when you can. Extra money comes straight off the balance, so less interest accrues for the rest of the loan.
- Round up the payment. Even a small fixed increase each month can shave months or years off the term.
- Watch the rate. On large balances, a fraction of a percent changes the total cost meaningfully.
This is general information, not financial advice — lenders differ on fees, early-repayment terms and how interest is applied.