Free Mortgage Calculator

Q: How accurate is this calculator?

It uses the same amortization formula as banks: M = P[r(1+r)^n]/[(1+r)^n-1]. The default interest rate and property tax are current averages for the US market. Your actual rate depends on your credit score, lender, and loan type. Use this as a starting point, then get pre-approved for your exact number.

Q: Should I put 20% down to avoid PMI?

Not necessarily. PMI costs 0.5-1% of the loan annually, but waiting years to save 20% means paying rent instead of building equity. Run both scenarios in the calculator to compare monthly payments. Often the difference is smaller than expected.

Q: What if interest rates change after I calculate?

Rates move daily. The calculator uses today's average, but you can manually enter any rate under More Options. Try your expected rate plus or minus 1% to see sensitivity.

Q: Can I trust this for a non-US market?

Each market has its own calculator with its own formulas. The German Hypothekenrechner calculates Zinsbindung and Kaufnebenkosten. These aren't translations — they're different financial products.

Q: Why does the calculator ask for income instead of loan amount?

Because the question 'can I afford this house?' starts with your income, not with the bank's offer. Most calculators assume you already know how much you want to borrow. This one helps you figure that out.

Enter your income and debt payments — see the maximum home price you can afford.

Your finances

Annual income

Monthly debt payments

Loans & credit cards only — not rent or groceries

Interest rate

Loan term

Down payment

You can afford up to

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How to Use This Calculator

First Home tab

The default tab. Enter your annual income and monthly debt payments — this includes car loans, student loans, and credit card minimum payments. Do not include rent (it will be replaced by your mortgage), groceries, or utilities. The calculator estimates the maximum home price you can comfortably afford, using a 28% front-end debt-to-income ratio. Expand "More options" to adjust the interest rate, loan term, and down payment percentage.

Refinance tab

For homeowners considering a rate change. Enter your current loan balance and current rate, then the new offered rate under "More options." You'll see the total savings over the remaining term and the difference in monthly payments.

Early Payoff tab

Enter your current loan balance and an extra monthly amount you'd like to pay on top. See how many years and dollars you'll save. Try different amounts to find the sweet spot between faster payoff and monthly comfort.

Share your result

Every input is encoded in the URL. Click Share, send the link to your partner — they'll open it and see your exact numbers. No re-entering, no screenshots.

The Formula

Your maximum home price is calculated from your debt-to-income ratio:

Max Monthly Payment = (Annual Income ÷ 12) × 0.28 − Existing Monthly Debts

From this monthly payment, the calculator derives the maximum loan amount using the standard amortization formula, then adds your down payment to get the purchase price.

For the US market, the calculation includes:

Property tax (estimated by state average)
Homeowner's insurance (0.35% of home value/year)
PMI if down payment < 20% (0.5–1% of loan/year)
HOA if applicable

The result is conservative. Banks may approve more — but "approved" and "comfortable" are different numbers. This calculator optimizes for comfortable.

Example

Sarah & Mike — Austin, TX

Combined income: $95,000. Monthly debt payments (car loan, credit cards): $500. Savings for down payment: $25,000.

First Home tab

Max affordable home$249,000

Down payment$25,000 (10%)

Loan amount$224,000

Monthly payment$1,416

PMI applies since down payment is under 20% — it drops off when they reach 20% equity. They found a townhouse for $235,000. Monthly payment: $1,337. Within budget.

Early Payoff tab

Mike suggests adding $300/month extra. Result: mortgage paid off in 18.5 years instead of 30. Total interest saved: $117,000. They agreed to start with $150/month — still saves 7 years and $76,000.

They clicked Share, sent the link to Sarah's dad (who offered to help with the down payment). He opened it on his phone — same numbers. Family discussion moved from "can they afford it?" to "which neighborhood?"

FAQ

How accurate is this calculator? ▼

It uses the same amortization formula as banks: M = P[r(1+r)ⁿ]/[(1+r)ⁿ−1]. The default interest rate and property tax are current averages for the US market. Your actual rate depends on your credit score, lender, and loan type. Use this as a starting point — then get pre-approved for your exact number.

Should I put 20% down to avoid PMI? ▼

Not necessarily. PMI costs 0.5–1% of the loan annually, but waiting years to save 20% means paying rent instead of building equity. Run both scenarios: enter your current savings as down payment, then enter 20%. Compare the monthly payments. Often the difference is smaller than expected.

What if interest rates change after I calculate? ▼

Rates move daily. The calculator uses today's average, but you can manually enter any rate in "More options." Try your expected rate ±1% to see how sensitive your payment is. If a 1% increase makes the payment unaffordable — you're stretching too far.

Can I trust this for a non-US market? ▼

Each market has its own calculator with its own formulas. The German Hypothekenrechner calculates Zinsbindung and Kaufnebenkosten. The Russian calculator includes matkapital. These aren't translations — they're different financial products. If your market is listed, the calculator is built for it.

Why does the calculator ask for income instead of loan amount? ▼

Because the question "can I afford this house?" starts with your income, not with the bank's offer. Most calculators assume you already know how much you want to borrow. This one helps you figure that out. If you already know the loan amount — switch to the Refinance or Early Payoff tab.

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