Mortgage Repayment Calculator
Estimate your repayments, see the total interest you'll pay, and discover how extra repayments can help you pay off your home loan sooner.
Last Updated: June 2026
Loan details
Your repayments
Monthly repayment
$3,792
Total interest paid
$765,267
Total repaid
$1,365,267
Loan balance over time
Repayment schedule (yearly)
| Year | Principal | Interest | Balance |
|---|---|---|---|
| 1 | $6,706 | $38,803 | $593,294 |
| 2 | $7,155 | $38,353 | $586,138 |
| 3 | $7,635 | $37,874 | $578,503 |
| 4 | $8,146 | $37,363 | $570,357 |
| 5 | $8,692 | $36,817 | $561,666 |
| 6 | $9,274 | $36,235 | $552,392 |
| 7 | $9,895 | $35,614 | $542,497 |
| 8 | $10,557 | $34,951 | $531,940 |
| 9 | $11,264 | $34,244 | $520,676 |
| 10 | $12,019 | $33,490 | $508,657 |
| 11 | $12,824 | $32,685 | $495,833 |
| 12 | $13,683 | $31,826 | $482,150 |
| 13 | $14,599 | $30,910 | $467,551 |
| 14 | $15,577 | $29,932 | $451,975 |
| 15 | $16,620 | $28,889 | $435,355 |
| 16 | $17,733 | $27,776 | $417,622 |
| 17 | $18,921 | $26,588 | $398,701 |
| 18 | $20,188 | $25,321 | $378,514 |
| 19 | $21,540 | $23,969 | $356,974 |
| 20 | $22,982 | $22,527 | $333,992 |
| 21 | $24,521 | $20,987 | $309,470 |
| 22 | $26,164 | $19,345 | $283,307 |
| 23 | $27,916 | $17,593 | $255,391 |
| 24 | $29,785 | $15,723 | $225,605 |
| 25 | $31,780 | $13,729 | $193,825 |
| 26 | $33,909 | $11,600 | $159,916 |
| 27 | $36,180 | $9,329 | $123,737 |
| 28 | $38,603 | $6,906 | $85,134 |
| 29 | $41,188 | $4,321 | $43,946 |
| 30 | $43,946 | $1,563 | $0 |
How This Calculator Works
This calculator uses the standard mortgage repayment formula to work out a fixed payment that clears your loan over the term you choose:
M = P × r × (1 + r)^n ÷ ((1 + r)^n − 1)
Here M is your repayment per period, P is the principal (amount borrowed), r is the interest rate per period (the annual rate divided by the number of payments per year), and n is the total number of payments.
Example:for a $500,000 loan at 6% annual interest over 30 years paid monthly, r = 0.06 ÷ 12 = 0.005 and n = 360. Plugging these into the formula gives a repayment of roughly $2,998 per month. Each repayment first covers the interest charged that month, and the remainder reduces your principal balance, which is how the loan is gradually paid off.
How mortgage repayments are calculated
Mortgage repayments are worked out using an amortisation formula that combines three factors: the amount you borrow (the principal), the interest rate, and the loan term. The formula calculates a fixed repayment that, paid consistently, clears the loan exactly at the end of the term.
In the early years, most of each repayment covers interest because your outstanding balance is high. As the balance falls, the interest portion shrinks and more of each repayment chips away at the principal. This is why the loan balance curve in the chart above starts gently and then drops more steeply over time.
Fixed vs variable rates
A fixed-rate mortgage locks your interest rate for an agreed period, giving you certainty over your repayments and protection if rates rise. The trade-off is less flexibility and potential break costs if you repay early or refinance.
A variable-rate mortgage moves with the market. Repayments can fall when rates drop, and these loans usually offer more flexible features such as offset accounts and unlimited extra repayments. The downside is that repayments can also rise, so it helps to keep a buffer in your budget.
How extra repayments affect your loan
Even small extra repayments can make a big difference. Because interest is charged on your remaining balance, every additional dollar you pay reduces the base on which future interest is calculated. Over a 25 or 30 year loan, that compounding effect can save a substantial amount of interest and cut years off your loan.
Try entering an extra repayment amount above to see how your payoff time and total interest change.