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Mortgage Calculator

Monthly payment, total interest and a full amortization schedule, plus taxes, insurance and PMI, so the number matches your real closing costs.

The short answer

A $450,000 home with 20% down on a 30-year loan at 6.66% costs $2,313.46 a month in principal and interest, plus about $600 a month for property tax and insurance. Over the full term the interest comes to $472,845, more than the $360,000 borrowed.

The purchase

$
$90,000
%

Below 20% you will usually pay mortgage insurance.

The loan

%

US mortgages compound monthly.

years
$

Goes straight against principal.

Carrying costs

$
$

Total monthly payment

$2,913.46

$2,313.46 principal and interest, plus $600.00 for tax and insurance.

What the house actually costs

Over the whole life of the loan, before tax and insurance.

Down payment: $90,000 (9.8%), Loan principal: $360,000 (39.0%), Interest: $472,845 (51.2%)

  • Down payment$90,000
  • Loan principal$360,000
  • Interest$472,845

Home price

$450,000.00

Down payment

20.0% of the price

− $90,000.00

Amount borrowed

$360,000.00

Total interest over the term

360 payments at 6.66%

$472,844.50

Total of all payments

$922,844.50

What you still owe, year by year

Early payments are mostly interest. The balance falls slowly at first, then quickly.

$0$100,000$200,000$300,000Yr 1Yr 6Yr 11Yr 16Yr 21Yr 26Yr 30

Hover the chart to read any year.

Show the mathThe payment formula and the full amortization schedule

The payment comes from the standard amortising formula, where i is the periodic rate and n the number of payments:

payment = P × i × (1 + i)ⁿ ÷ ((1 + i)ⁿ − 1)

P = $360,000
i = 0.555000% per month
n = 360 payments
payment = $2,313.46

US mortgages compound monthly, so the periodic rate is simply the annual rate divided by 12.

Year by year, here is how each payment splits.

Amortization schedule by year
YearInterestPrincipalBalance
1$23,858$3,903$356,097
2$23,590$4,171$351,926
3$23,304$4,458$347,468
4$22,998$4,764$342,704
5$22,671$5,091$337,613
6$22,321$5,441$332,173
7$21,947$5,814$326,359
8$21,548$6,213$320,145
9$21,121$6,640$313,505
10$20,665$7,096$306,409
11$20,178$7,583$298,826
12$19,657$8,104$290,722
13$19,101$8,661$282,061
14$18,506$9,255$272,806
15$17,871$9,891$262,915
16$17,191$10,570$252,344
17$16,465$11,296$241,048
18$15,690$12,072$228,977
19$14,861$12,901$216,076
20$13,975$13,787$202,289
21$13,028$14,733$187,556
22$12,016$15,745$171,811
23$10,935$16,826$154,985
24$9,780$17,982$137,003
25$8,545$19,217$117,786
26$7,225$20,536$97,250
27$5,815$21,947$75,303
28$4,308$23,454$51,850
29$2,697$25,064$26,785
30$976$26,785$0

What this does not include

Closing costs, land transfer tax, legal fees, appraisal, title insurance, condo or HOA fees, and maintenance. Property tax and home insurance are your estimates, not quotes, and both change yearly.

Questions

What people ask

Why is so much of my early payment interest?

Interest is charged on what you still owe, and at the start you owe almost everything. The payment stays the same, so as the balance falls the interest share falls with it and the principal share grows. The crossover on a 30-year loan usually comes somewhere around year 18.

What is PMI and when does it stop?

Private mortgage insurance is charged when you put down less than 20%. It protects the lender, not you. You can usually request cancellation once you reach 20% equity, and it must be removed automatically at 22% under the Homeowners Protection Act.

Does paying extra each month really help?

Yes, and more than people expect, because every extra dollar goes straight against principal and stops accruing interest for the whole remaining term. The calculator shows exactly how many months it removes.

Should I take a 15-year mortgage instead?

The payment is much higher but the total interest is far lower, and 15-year rates are usually a little cheaper. Set the term to 15 and compare the total interest figures. That difference is what the shorter term buys you.

Keep going

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United States tax figures for 2026, last reviewed August 1, 2026. Every rate used here is listed with its source on the official rates page.