Mortgage Calculator — Monthly Payment & Amortisation
A mortgage calculator works out your monthly home-loan payment from the loan amount, interest rate and loan term — including property taxes, home insurance and PMI where they apply.
Year-by-year amortisation
| Year | Interest paid | Principal paid | Balance left |
|---|---|---|---|
| 1 | $20,644 | $5,284 | $314,716 |
| 2 | $20,291 | $5,637 | $309,079 |
| 3 | $19,913 | $6,015 | $303,064 |
| 4 | $19,510 | $6,418 | $296,646 |
| 5 | $19,080 | $6,848 | $289,799 |
| 6 | $18,622 | $7,306 | $282,493 |
| 7 | $18,133 | $7,795 | $274,697 |
| 8 | $17,610 | $8,318 | $266,380 |
| 9 | $17,053 | $8,875 | $257,505 |
| 10 | $16,459 | $9,469 | $248,036 |
| 11 | $15,825 | $10,103 | $237,933 |
| 12 | $15,148 | $10,780 | $227,154 |
| 13 | $14,426 | $11,502 | $215,652 |
| 14 | $13,656 | $12,272 | $203,380 |
| 15 | $12,834 | $13,094 | $190,286 |
| 16 | $11,957 | $13,971 | $176,316 |
| 17 | $11,022 | $14,906 | $161,409 |
| 18 | $10,023 | $15,905 | $145,505 |
| 19 | $8,958 | $16,970 | $128,535 |
| 20 | $7,822 | $18,106 | $110,429 |
| 21 | $6,609 | $19,319 | $91,110 |
| 22 | $5,315 | $20,613 | $70,497 |
| 23 | $3,935 | $21,993 | $48,504 |
| 24 | $2,462 | $23,466 | $25,038 |
| 25 | $890 | $25,038 | $0 |
How it works
- Enter the home price, deposit, interest rate and loan term.
- Add yearly taxes, insurance and PMI if you know them.
- See your monthly payment instantly, with a year-by-year breakdown of interest and principal.
Formula
Worked example
A $320,000 loan at 6.5% interest over 25 years (300 monthly payments) costs $2,160.66 a month for principal and interest, with total interest of about $328,199 over the life of the loan. Try your own numbers above.
Frequently asked questions
How much house can I afford?
A common guide is a home price around 3 to 4 times your yearly income, with total housing costs under about 28% of your gross monthly income. Your lender will also look at debts, credit and deposit.
How is a monthly mortgage payment calculated?
The payment is based on the loan amount, the monthly interest rate and the number of payments, using the amortisation formula shown above. Taxes, insurance and PMI are added on top.
What is PMI on a mortgage?
Private mortgage insurance (PMI) is usually required when your deposit is under 20% of the home price. It protects the lender, not you, and is added to your monthly payment until you have enough equity.
How much interest will I pay on a mortgage?
It depends on the rate and term. On a $320,000 loan at 6.5% over 25 years, total interest is about $328,199 — more than the loan itself. A shorter term or lower rate cuts this sharply.
Should I choose a 30-year or 15-year mortgage?
A 15-year loan has much higher monthly payments but far less total interest. A 30-year loan costs less per month but much more interest overall. Compare both in the calculator.
Does extra payment reduce my mortgage?
Yes. Even a small extra monthly payment goes straight to principal, cutting total interest and shortening the loan. The amortisation table above shows the effect year by year.