Principal, Interest, Taxes and Insurance — the four parts of a full monthly mortgage payment. GKCalculators shows all four so your estimate matches lender quotes.

How much should my down payment be?

20% avoids PMI on conventional loans, but many buyers put down less. Try different amounts and watch how the payment and total interest change instantly.

What formula does the Mortgage Calculator use?

It calculates using M = P · r(1+r)^n / ((1+r)^n − 1). The guide above walks through what each part means with a worked example.

How accurate is the Mortgage Calculator?

It uses standard, widely-accepted financial formulas, so the math is exact for the figures you enter. Real-world numbers can differ once lenders, taxes, fees and rounding are applied, so treat the result as a close estimate rather than a formal quote.

Does the Mortgage Calculator include taxes and fees?

It includes only the fields shown on the form. Where inputs for extra costs (fees, taxes, insurance) are available, add them for a fuller picture — a real quote may still vary by provider.

Is this calculator free to use?

Yes — every GKCalculators calculator is 100% free with no sign-up required. Create a free account only if you want to save your calculation history across devices.

All calculations run instantly in your browser. Nothing is sent anywhere unless you tap ‘Explain my results’ (AI) or ‘Save’ while signed in.

Can I share my result?

Yes. Tap Share and we copy a link with your exact inputs baked in, so anyone who opens it sees the same result.

Mortgage Calculator

#1 Popular

Monthly principal & interest, taxes, insurance, PMI and a full amortization schedule.

Compare

Currency

Home price

Down payment20.0%

Loan term (yrs)

Interest rate %

Property tax /yr

Insurance /yr

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Monthly payment

$2,548

$2,023 principal & interest + $525 tax & insurance

Loan amount

$320,000

Total interest

$408,142

Total of payments

$728,142

Principal Interest Tax Insurance

AI Breakdown & Smart Takeaway

Plain-English insight on your numbers

Get a personalized explanation of what these results mean — and how to improve them.

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How the Mortgage Calculator works

The GKCalculators Mortgage Calculator breaks down your monthly home loan payment into its principal, interest, taxes, insurance, and PMI components, then generates a full amortization schedule so you can see exactly how every dollar is applied over the life of your loan. It's built for prospective homebuyers, existing homeowners exploring refinancing, and anyone who wants a transparent, line-by-line view of how a mortgage actually works.

Your monthly payment is driven by the loan amount (price minus down payment), the interest rate, and the number of monthly payments (years × 12).

We split every payment into principal and interest and build a full amortization schedule — early payments are mostly interest, later ones mostly principal.

Property tax, home insurance and PMI are added on top to show the true ‘all-in’ monthly cost most banks quote.

Formula

M = P · r(1+r)^n / ((1+r)^n − 1)

Pro tips

Add extra to principal each month to cut years and tens of thousands in interest.
Compare a 15-year vs 30-year term — the shorter term saves huge interest for a higher payment.

Key terms

Amortization: — The process of spreading a loan's repayment across scheduled, equal periodic payments that cover both principal reduction and interest charges over the full loan term.
Principal: — The outstanding balance of the home loan that you actually borrowed, separate from any interest, taxes, or insurance costs.
Private Mortgage Insurance (PMI): — A lender-required insurance policy that protects the lender—not the borrower—against default risk when the down payment is less than 20% of the property's purchase price.
PITI: — An acronym for Principal, Interest, Taxes, and Insurance—the four components that together constitute a borrower's total monthly mortgage payment.
Loan-to-Value Ratio (LTV): — The ratio of the mortgage loan amount to the appraised value of the property, expressed as a percentage; an LTV above 80% typically triggers PMI requirements.
Escrow: — A lender-managed account into which a portion of each monthly payment is deposited to cover future property tax and homeowner's insurance bills on your behalf.