Mortgage Calculator

Calculate your monthly payment, total interest, and full amortization schedule

$
$
= 10.0% of home price
%
+ Add Property Tax, Insurance & HOA
%
$
$
Monthly Payment (P&I)
Loan Amount
Down Payment
Total Interest
Total Cost

How the Mortgage Calculator Works

This calculator uses the standard amortization formula to compute your monthly principal and interest payment:

M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1]
  • M = monthly payment
  • P = loan amount (home price − down payment)
  • r = monthly interest rate (annual rate ÷ 12 ÷ 100)
  • n = total number of payments (years × 12)

Property tax, home insurance, HOA, and PMI are added on top of this P&I payment to give you the total monthly housing cost.

What Makes Up Your Monthly Payment? (PITI + PMI)

ComponentWhat It IsTypical Range
PrincipalPortion that reduces your loan balanceGrows over time
InterestCost of borrowing — paid to lenderShrinks over time
Property TaxAnnual tax ÷ 12, collected in escrow0.5%–2.5% of home/yr
InsuranceHomeowners insurance, collected in escrow$800–$2,000/yr avg
PMIRequired if down payment < 20%0.5%–1.5% of loan/yr
HOAHomeowners association fee (if applicable)$0–$500+/month

30-Year vs 15-Year Mortgage: What's the Difference?

Factor30-Year Fixed15-Year Fixed
Monthly PaymentLowerHigher (~40% more)
Total Interest PaidMuch higherMuch lower (~50% less)
Equity BuildupSlowTwice as fast
Interest RateHigherUsually 0.5–1% lower
Cash Flow FlexibilityMore (lower payment)Less (higher payment)
Best ForMax monthly flexibilityMin total interest cost

On a $300,000 loan at 6.5%, the 30-year monthly payment is ~$1,896 with ~$382,000 total interest. The 15-year payment is ~$2,613 but total interest is only ~$170,000 — saving over $210,000.

Down Payment Impact on a $350,000 Home (6.5% / 30yr)

Down PaymentDown ($)Loan AmountMonthly P&IPMI?Total Interest
3%$10,500$339,500$2,147Yes ~$141/mo$432,985
5%$17,500$332,500$2,103Yes ~$138/mo$424,074
10%$35,000$315,000$1,993Yes ~$131/mo$402,070
20%$70,000$280,000$1,770No$357,395
25%$87,500$262,500$1,660No$335,058
30%$105,000$245,000$1,549No$312,720

Frequently Asked Questions

How is a monthly mortgage payment calculated?

The formula is M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1], where P is the loan amount, r is the monthly interest rate (annual rate ÷ 12), and n is the number of payments (years × 12). This gives the principal and interest portion. Property tax, insurance, and PMI are added on top for the full monthly payment.

What is PMI and when can I remove it?

PMI (Private Mortgage Insurance) is required when your down payment is less than 20%. It typically costs 0.5%–1.5% of the loan per year. You can request PMI cancellation once your equity reaches 20%, and lenders must automatically remove it at 22% equity under the federal Homeowners Protection Act.

Is a 30-year or 15-year mortgage better?

A 15-year mortgage saves significantly more in total interest and builds equity faster, but the monthly payment is roughly 40% higher. A 30-year mortgage has lower monthly payments for more cash flow flexibility but costs far more in total interest over the life of the loan. Use the preset buttons above to compare both scenarios for your home price.

How much house can I afford?

The standard guideline is the 28/36 rule — keep total housing costs (P&I + tax + insurance) under 28% of gross monthly income, and total debt under 36%. A household earning $7,000/month should keep total housing payment under ~$1,960/month. Lenders also evaluate credit score, DTI ratio, employment history, and savings.

What interest rate should I enter?

Use the rate quoted by your lender or mortgage broker. Current 30-year fixed rates vary by credit score, loan type, and market conditions. Even a 0.5% difference on a $300,000 loan changes your payment by ~$90/month and ~$32,000 in total interest — always shop multiple lenders.

Does this calculator include taxes and insurance?

Yes — click "Add Property Tax, Insurance & HOA" to include these. The default P&I calculation shows principal and interest only. Add your estimated property tax rate (1%–2% is common in most US states), annual insurance premium (~$1,200 average), and HOA if applicable for your complete monthly payment.

What is an amortization schedule?

Amortization shows how each payment is split between principal and interest over time. Early in a 30-year loan, most of your payment is interest — on a $300,000 loan at 6.5%, your first payment of $1,896 is roughly $1,625 interest and only $271 principal. Over time this reverses. The table above shows your balance at the end of each year.

Can I pay off my mortgage early?

Yes — any extra payment goes directly toward principal, reducing future interest. Use our Mortgage Payoff Calculator to see exactly how many years you save and total interest reduction from extra monthly payments. Even $100–$200/month extra can save years and tens of thousands in interest.

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