🏠Mortgage Calculator
Enter loan amount, term, and interest rate to quickly calculate monthly payments and interest. Supports both equal principal & interest and equal principal repayment methods.
| Period | Payment (CNY) | Principal (CNY) | Interest (CNY) | Remaining Balance (CNY) |
|---|
Related guide
Mortgage, Interest and Percentage Calculators, and the Numbers They Do Not Show You
The mortgage page recomputes as you type, the interest page waits for a button, and the percentage page answers a division by zero with 0%. Everything below was read out of each page's own script: the annuity formula, the rounding drift in the repayment table, the growth-curve point that lands a year past your term, and the axis label that is ten times off.
The two repayment methods
Nearly every mortgage in the world is one of two shapes, and the difference is worth understanding before you look at the numbers, because both are offered here and they behave quite differently.
Equal Principal & Interest is the annuity method: the payment is fixed for the whole term, with the split between interest and principal shifting as the balance falls. Early payments are almost entirely interest; late ones are almost entirely principal. It is the more common arrangement because the fixed payment is easier to budget for, and it costs more in total interest.
Equal Principal does the opposite: the principal repaid each month is constant, and the interest is charged on whatever balance remains. That makes the payment highest in the first month and lower every month after, falling by a fixed amount. Total interest is lower than the annuity method and the early payments are noticeably higher.
Reading the results
The headline figure is the monthly payment under the equal payment method, or the first month's payment under equal principal, and the line beneath it tells you which. Alongside it you get the total repaid over the term, the total interest as an amount, and the interest as a share of everything you pay. For equal principal there is an extra line showing how much the payment drops each month.
The amortisation table below breaks the loan down period by period, showing what each payment consists of and what is left owing. It is summarised by year by default and can be switched to monthly, and it ends with a total row so the yearly figures can be checked against the headline numbers.
The interest share is the number to look at first. It answers the question a monthly payment hides: a long term lowers the payment and raises the total interest, and the ratio makes that trade-off visible in a way the payment figure alone does not.
Conventions and limits
Two conventions are worth stating plainly. The monthly rate is the annual rate divided by twelve, which is the nominal convention used in most lending rather than an effective annual rate; if a lender quotes an APR that includes fees, this calculator will not match it. And nothing here accounts for arrangement fees, insurance, taxes or a rate that changes over the term — it models a fixed-rate loan and only that.
On the input side, the term is capped at thirty years, and the amount is entered in units of ten thousand, so a figure of 100 means one million. Results are labelled in CNY, a convention carried over from this site's Chinese edition; the arithmetic is currency-agnostic, so enter a number and read the output in whichever currency you are actually modelling, but be aware the labels are fixed.
A rate of zero is rejected. The formulas would handle it, but the page requires a positive rate, so an interest-free loan cannot be modelled here.
FAQ
Which repayment method costs less overall?
Equal principal, always, because the balance falls faster and less interest accrues. The trade-off is that its payments start higher — sometimes by a third or more — so it suits a borrower who can afford the early years and wants to minimise the total cost.
Why is the amount entered in units of ten thousand?
That is a convention carried over from the Chinese edition, where loan amounts are conventionally discussed in units of ten thousand. Enter 100 for one million, or 30 for three hundred thousand if you are modelling a smaller loan.
Why is the result labelled CNY?
Again a carry-over from the Chinese edition. The calculation has no currency in it at all — the numbers mean whatever unit you put in — but the labels on the page are fixed in CNY rather than being selectable.
Can I model a 0% loan?
No. The page requires a positive interest rate, so an interest-free or promotional-rate loan cannot be entered. For a rough figure, use a very small rate such as 0.1% and read the total repayment rather than the interest.
Does it include fees, insurance or taxes?
No. It models principal and interest only, at a fixed rate for the whole term. Real repayments often include escrow for taxes and insurance and may carry arrangement fees, so treat the output as the loan itself rather than your total monthly outgoings.
How does it compare with my lender's figure?
Expect a small difference. The monthly rate here is the annual rate divided by twelve, which is the usual nominal convention; if the lender quotes an effective annual rate that accounts for compounding within the year, their payment will come out slightly higher. The same applies to any quoted APR that bundles fees into the rate.