Just enter the loan amount, annual rate, and repayment term to quickly compute the monthly payment, total repayment, and total interest.
Input Data
Results
At a glance:A simple mortgage amortises the principal with interest; the monthly payment, total repayment, and total interest follow the standard loan formula.
Formula
monthlyPayment = P × r·(1+r)^n / ((1+r)^n − 1) (r = annualRate%/12, n = termYears×12)
totalRepayment = monthlyPayment × n
totalInterest = totalRepayment − P
$$\\text{Monthly payment} = P \\times \\dfrac{r(1+r)^n}{(1+r)^n - 1}$$$$\\text{Total repayment} = \\text{Monthly payment} \\times n, \\quad \\text{Total interest} = \\text{Total repayment} - P$$$$r = \\dfrac{\\text{Annual rate}\\%}{12}, \\quad n = \\text{Term (years)} \\times 12$$How to Use
- Enter the loan amount, annual rate, and term.
- Review the monthly payment, total repayment, and total interest.
FAQ
How is this different from the full mortgage calculator?
The simple mortgage calculator needs only three inputs — loan amount, rate and term — for a quick estimate of the monthly payment. The full mortgage calculator can also handle the down-payment ratio, mortgage insurance, stamp duty and early repayment. If you just want the monthly payment and total interest, this tool is the most convenient.
How does a rate rise affect the payment?
Hong Kong mortgages are mostly floating-rate; a rise immediately lifts the monthly payment and total interest. Try different rates to see the impact and keep a buffer for rate swings; banks also apply a stress test at higher rates when approving.
Is a longer term better?
A longer term lowers the monthly payment and eases cash flow, but with a longer interest period the total interest rises markedly. Balance an affordable monthly payment against the overall interest cost, and note Hong Kong mortgage terms are usually limited by building age and borrower age.
Will the result match the bank's actual approval?
The direction and magnitude are reliable, but the actual payment and borrowable amount are affected by several factors this tool does not include, so treat it as a preliminary estimate. First, it assumes a fixed rate, but Hong Kong mortgages are mostly floating (H-PLAN tracking interbank rates, P-PLAN tracking prime), so the monthly payment and total interest move with the market — run again at a higher rate to simulate a rise. Second, it computes only the payment, not mortgage insurance (for high-ratio loans), stamp duty, legal or valuation fees. Third, how much you can borrow also depends on the bank's debt-servicing-ratio (DSR) cap and the interest-rate stress test, not just the payment figure. Fourth, the bank's actual accrual and rounding may differ slightly from this simplified model. Use it to grasp the payment burden and compare options; the actual approval and payment follow the bank's quote and HKMA guidance.
What share of income should the monthly payment be for safety?
A common prudent rule is to keep the payment-to-income ratio from getting too high, with a buffer for rate rises and surprises. In Hong Kong, banks already cap the debt-servicing ratio (DSR) by property price and whether it is owner-occupied, and apply an interest-rate stress test — whether your payment stays within the allowed ratio after a assumed rise. Even if approved, keep total debt payments (mortgage plus others) at a comfortable level with room to save and handle emergencies. Practically: compute the payment at the current rate, then again at 2%–3% higher; only if you can afford the higher-rate payment is the borrowing amount safe. Also keep an emergency fund (commonly 3–6 months of expenses). The specific DSR cap and stress-test rules follow the bank and HKMA's latest guidance.
Content review: Calculatorism Finance Team. Results are for reference only; please refer to the relevant authorities for the official figures.