Mortgage calculator

Work out the monthly cost of a home loan, including the extras that are easy to forget.

Monthly payment

$1,516.96

Loan amount: $240,000.00
Down payment: $60,000.00
Loan payment (principal and interest): $1,516.96
Total interest over the loan: $306,106.77

Where the money goes

Amount borrowed $240,000.00 43.9%
Interest $306,106.77 56.1%

Balance left at the end of each year

Show the steps

Loan amount = home price − down payment = $300,000.00 − $60,000.00 = $240,000.00
Monthly interest rate: annual rate ÷ 12 = 0.541667% (as a decimal, r = 0.00541667)
Number of payments: n = 360
Payment = P × r ÷ (1 − (1 + r)^−n) = 240,000 × 0.00541667 ÷ (1 − 0.143025) = $1,516.96
Total interest = all payments − amount borrowed = $546,106.77 − $240,000.00 = $306,106.77

Year by year table

Year	Principal paid	Interest paid	Balance left
1	$2,682.54	$15,521.02	$237,317.46
2	$2,862.20	$15,341.36	$234,455.26
3	$3,053.88	$15,149.68	$231,401.38
4	$3,258.41	$14,945.15	$228,142.97
5	$3,476.63	$14,726.93	$224,666.35
6	$3,709.46	$14,494.09	$220,956.88
7	$3,957.89	$14,245.67	$216,998.99
8	$4,222.96	$13,980.60	$212,776.03
9	$4,505.78	$13,697.78	$208,270.24
10	$4,807.54	$13,396.02	$203,462.70
11	$5,129.51	$13,074.05	$198,333.19
12	$5,473.04	$12,730.51	$192,860.15
13	$5,839.58	$12,363.97	$187,020.56
14	$6,230.67	$11,972.89	$180,789.89
15	$6,647.95	$11,555.61	$174,141.94
16	$7,093.18	$11,110.38	$167,048.76
17	$7,568.22	$10,635.34	$159,480.54
18	$8,075.08	$10,128.48	$151,405.46
19	$8,615.88	$9,587.68	$142,789.58
20	$9,192.90	$9,010.66	$133,596.68
21	$9,808.57	$8,394.99	$123,788.11
22	$10,465.47	$7,738.09	$113,322.64
23	$11,166.36	$7,037.20	$102,156.28
24	$11,914.19	$6,289.37	$90,242.09
25	$12,712.11	$5,491.45	$77,529.99
26	$13,563.46	$4,640.10	$63,966.53
27	$14,471.83	$3,731.73	$49,494.70
28	$15,441.03	$2,762.53	$34,053.67
29	$16,475.15	$1,728.41	$17,578.52
30	$17,578.52	$625.04	$0.00

How to use the mortgage calculator

Enter the price of the home, the share you will pay up front as a down payment, the interest rate and the length of the loan. The result is the monthly payment of principal and interest.

The three optional boxes let you add yearly property tax, yearly home insurance and any monthly fees such as a service charge or homeowners association dues. With those filled in, the headline figure is closer to what will actually leave your account each month.

The formula

The loan amount is the home price minus the down payment. The payment on that loan uses the standard formula:

Payment = P × r ÷ (1 − (1 + r)⁻ⁿ)

with r as the monthly rate and n as the number of monthly payments. Yearly tax and insurance are divided by 12 and added on top.

Worked example

A 300,000 home with 20% down leaves a loan of 240,000. At 6.5% over 30 years the principal and interest payment is 1,516.96 a month. With 3,600 a year in property tax and 1,200 in insurance, the total rises to 1,916.96.

Results are estimates for planning. They are not financial advice, and a lender’s own figures may differ because of fees and rounding.

Common questions

How much difference does a bigger down payment make?

A lot. It shrinks the loan, so both the monthly payment and the total interest fall. Change the down payment box and watch the total interest row.

Is a 15-year loan cheaper than a 30-year one?

The monthly payment is higher, but the total interest is far lower because the money is borrowed for half as long.

Does this work for a variable rate?

It assumes the rate stays the same. For a variable rate, treat the result as the payment at today's rate and test a higher rate to see what you could afford.

Mortgage calculator by StepCalcs