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Mortgage Calculator

Calculate your monthly mortgage payment, total interest cost, and full amortization schedule. Enter the home price, interest rate, and loan term — results update instantly.

Down: $80,000 — Loan: $320,000

Monthly Payment
$2,128.97
Principal + Interest only
$766,428
Total Payment
$446,428
Total Interest
$320,000
Loan Principal

Yearly Amortization Schedule

YearPrincipal PaidInterest PaidRemaining Balance
1$3,251$22,297$316,749
2$3,486$22,062$313,264
3$3,738$21,810$309,526
4$4,008$21,540$305,519
5$4,297$21,250$301,221
6$4,608$20,939$296,613
7$4,941$20,606$291,672
8$5,298$20,249$286,373
9$5,681$19,866$280,692
10$6,092$19,455$274,600
11$6,533$19,015$268,067
12$7,005$18,543$261,062
13$7,511$18,036$253,551
14$8,054$17,493$245,497
15$8,636$16,911$236,860
16$9,261$16,287$227,600
17$9,930$15,617$217,669
18$10,648$14,900$207,021
19$11,418$14,130$195,603
20$12,243$13,304$183,360
21$13,128$12,419$170,232
22$14,077$11,470$156,155
23$15,095$10,453$141,060
24$16,186$9,361$124,873
25$17,356$8,191$107,517
26$18,611$6,937$88,906
27$19,956$5,591$68,950
28$21,399$4,149$47,551
29$22,946$2,602$24,605
30$24,605$943$0

How Mortgage Amortization Works

Amortization means paying off your loan through fixed monthly payments over time. Each payment covers both interest (cost of borrowing) and principal (reducing the balance you owe). The split changes every month — early payments are mostly interest, while later payments shift toward principal.

The formula used is M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments (years × 12).

Year 1

Up to 80–85% of each payment goes to interest. Principal paydown is slow.

Midpoint

At the halfway mark, the interest/principal split reaches roughly 50/50.

Final years

Most of each payment goes to principal. Your equity grows rapidly.

Mortgage Comparison

Monthly payments and total cost for a $400,000 home with 20% down ($320,000 loan) at different interest rates.

Rate15-yr/mo15-yr total30-yr/mo30-yr total
6%$3,375$607,500$2,398$863,280
6.5%$3,484$627,120$2,528$910,080
7%$3,593$646,740$2,661$957,960
7.5%$3,705$666,900$2,797$1,006,920

Principal + interest only. Excludes property taxes, insurance, and PMI.

Frequently Asked Questions

How is a monthly mortgage payment calculated?▾
The monthly payment uses the amortization formula: M = P×[r(1+r)^n] / [(1+r)^n - 1], where P = loan principal, r = monthly interest rate (annual rate ÷ 12), and n = total number of payments (years × 12). This formula ensures equal monthly payments throughout the loan term while gradually shifting from interest-heavy to principal-heavy payments.
What is a good mortgage interest rate in 2026?▾
As of early 2026, 30-year fixed mortgage rates in the US range from 6.5% to 7.5% depending on credit score, down payment, and lender. A rate below 6.5% is considered excellent. Rates above 7.5% indicate either a lower credit score or unfavorable market conditions. Always compare quotes from at least 3 lenders.
How much does a $400,000 mortgage cost per month?▾
At 7% annual rate with a 30-year term, a $400,000 mortgage costs approximately $2,661/month (principal + interest only). Over 30 years, total payments reach about $958,000 — meaning you pay $558,000 in interest. A 15-year term at the same rate gives $3,593/month but saves $240,000+ in total interest.
What is the difference between the 15-year and 30-year mortgage?▾
A 15-year mortgage has higher monthly payments (typically 30–40% higher) but significantly lower total interest paid — often 40–50% less. You build equity faster. A 30-year mortgage has lower monthly payments, giving more cash flow flexibility. The best choice depends on your financial goals: debt freedom vs. monthly cash flow.
Does a down payment affect the mortgage calculation?▾
Yes. Your mortgage principal equals home price minus down payment. A 20% down payment on a $400,000 home means a $320,000 mortgage. A larger down payment also typically removes the requirement for PMI (private mortgage insurance), which adds 0.5–1.5% annually to borrowing costs for down payments under 20%.
What is an amortization schedule?▾
Amortization is the process of paying off debt through regular scheduled payments. In the early years of a mortgage, most of your payment goes to interest. Over time, the principal portion increases and interest decreases. This calculator shows a yearly amortization summary — you can see the remaining balance after each year and how much of your payments went to principal vs. interest.
Does this calculator include property taxes and insurance?▾
No — this calculator shows principal and interest only (P&I). Your actual monthly housing cost (PITI) also includes property taxes (typically 1–1.5% of home value annually), homeowner's insurance (~$100–200/month), and PMI if applicable. Add approximately $500–900/month for taxes and insurance on a typical US home purchase.