Mortgage Payment Calculator
Enter the amount, the rate you have been quoted and the term, and this gives you the monthly payment along with what the loan costs in total. The rate is yours to type in — nothing here is a published average.
Monthly payment
$1,896.20per month
- Monthly payment
- $1,896.20
- Total interest
- $382,633.47
- Total repaid
- $682,633.47
- Term
- 30 years
- First month interest
- $1,625.00
- First month principal
- $271.20
- Over the full term the interest comes to more than the amount borrowed. Shortening the term or paying extra changes that sharply.
- Principal and interest only. Fees, insurance and any taxes a lender bundles into the quoted figure are separate from the loan itself.
- Assumes a fixed rate for the whole term and every payment made on time.
About the mortgage payment calculator
A fixed-rate mortgage payment never changes, but what it does changes every single month. Early on, almost all of it is interest and barely any touches the balance. By the end that has reversed. This shows both the payment and that split, because the split is what most people have never seen.
On a $300,000 loan at 6.5%, the payment is about $1,896 a month. The first payment includes $1,625 of interest and puts only $271 against the balance. Over thirty years the interest comes to more than the house cost — which is the number that tends to change how people think about the term they choose.
This covers principal and interest only. Property taxes, buildings insurance and any mortgage insurance are real money and often add a third again to the monthly figure, but they are separate from the loan and vary by where you live.
What it works out
- The monthly principal and interest payment
- Total interest and total repaid over the term
- How the first payment splits between the two
- Any rate and any term, fixed-rate
The formula
M = P × r(1 + r)ⁿ ÷ ((1 + r)ⁿ − 1)
This is the standard amortization formula, and every fixed-rate lender in the world uses it. P is the amount borrowed, r is the monthly interest rate — the annual rate divided by twelve — and n is the number of monthly payments.
The reason it looks awkward is that it is solving a circular problem. Each month's interest depends on the balance, the balance depends on how much the last payment took off it, and that depends on the interest. The formula is what falls out when you insist that the same payment clears the loan exactly on the final month.
A rate of zero breaks it, because the whole expression divides by zero. Interest-free finance is a real thing, so this calculator handles that case separately and simply divides the amount by the number of months.
Watch what the rate does. The payment does not rise in proportion to it: going from 5% to 6.5% on a thirty-year loan raises the monthly figure by about 18%, but raises the total interest by nearly 30%, because the extra is charged for longer on a balance that falls more slowly.
- P
- The amount borrowed, after any deposit.
- r
- The monthly interest rate — the annual rate divided by 12, so 6.5% a year is 0.5417% a month.
- n
- The number of monthly payments. Thirty years is 360.
- M
- The monthly payment, covering principal and interest only.
A worked example
Three hundred thousand borrowed at 6.5% over thirty years.
That works out to $1,896.20 per month.
- Monthly payment
- $1,896.20
- Total interest
- $382,633.47
- Total repaid
- $682,633.47
- Term
- 30 years
- First month interest
- $1,625.00
- First month principal
- $271.20
Questions
What is the monthly payment on a $300,000 mortgage?
About $1,896 a month at 6.5% over thirty years, covering principal and interest. At 5% it would be $1,610 and at 8% it would be $2,201, which is how much a rate move is worth on a loan that size.
Why is my lender quoting more than this?
Because most quotes bundle in property taxes, buildings insurance and often mortgage insurance. Those are real costs but they are not the loan, and they vary enormously by location, so they are not included here.
Why is so much of my early payment interest?
Interest is charged on the balance outstanding, and at the start the balance is the whole loan. On a $300,000 mortgage at 6.5%, the first month accrues $1,625 of interest against an $1,896 payment, leaving $271 to reduce the balance. As the balance falls the split shifts, slowly at first and then quickly.
Does a shorter term really save that much?
Substantially. The same $300,000 at 6.5% over fifteen years costs about $2,613 a month — 38% more — but the total interest drops from roughly $383,000 to about $170,000. You pay more each month for less than half the total interest.
What is amortization?
It is the schedule by which a loan is paid off in equal instalments, with each one covering the interest accrued since the last and putting whatever is left against the balance. It is why the payment stays flat while what it buys you changes every month.
Does this work for other loans?
Yes. The maths is identical for car finance, personal loans and student loans — only the amounts and terms differ. There are dedicated pages for those with more suitable defaults.
What if my rate is variable?
This assumes a fixed rate for the whole term. For a variable or tracker rate, run it at the current rate to see today's payment, then again a few points higher to see what a rise would cost you. That second number is the one worth knowing before you commit.