First-Time Home Buyer Calculator

Compare different down payment strategies side-by-side. See how 3.5%, 5%, 10%, and 20% down affect your monthly payment, PMI costs, and total interest over the life of your loan.

How to Use This Calculator

This calculator helps first-time buyers understand how different down payment amounts affect their mortgage. We've preloaded 4 scenarios for a $350,000 home with current market rates.

Pre-Loaded Scenarios:

  • 3.5% Down (FHA): Minimum down payment for FHA loans, includes PMI
  • 5% Down (Conventional): Low down payment option with PMI
  • 10% Down: Mid-range option, still includes PMI
  • 20% Down: No PMI required, lowest total cost

What You'll See

  • • Monthly payment breakdown (P&I, PMI, taxes, insurance)
  • • Total interest paid over 30 years
  • • When PMI drops off (at 20% equity)
  • • Full amortization schedules
  • • Side-by-side comparison charts

Customize Your Scenarios

  • • Adjust purchase price to match your market
  • • Update interest rates to current offers
  • • Change property tax and insurance estimates
  • • Add extra payments to pay off faster
  • • Save scenarios for later comparison

Understanding PMI (Private Mortgage Insurance)

If you put down less than 20%, you'll pay PMI until you reach 20% equity. PMI protects the lender and typically costs 0.5-1% of the loan amount annually.

Good news: PMI automatically drops off when you reach 20% equity through principal payments or home appreciation. This calculator shows exactly when that happens for each scenario.

Which Down Payment is Right for You?

3.5% Down (FHA) - Best if:

You're tight on cash for closing and want to preserve savings. FHA loans are easier to qualify for with lower credit scores.

5-10% Down - Best if:

You want to balance upfront costs with monthly payments. Good middle ground between saving cash and reducing PMI.

20% Down - Best if:

You have the cash saved and want the lowest monthly payment with no PMI. Saves the most money long-term and gives you instant equity.

Enter Your Details

Provide your information to generate personalized down payment scenarios

$

The home price you're considering

%

Current rate you've been quoted (we'll automatically adjust for better rates with higher down payments)

%/year

Annual % of home value

%/year

Annual % of home value

%/year

Historical average is ~3-4% annually (affects when PMI drops off)

What happens next: We'll generate 4 scenarios comparing 3.5%, 5%, 10%, and 20% down payments using your information. You can still edit any scenario individually after they're created.

Need More Flexibility?

The Mortgage Modeler gives you complete control to build any scenario from scratch. Model ARMs, refinances, extra payments, and compare unlimited scenarios.

Open Mortgage Modeler
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Powerful mortgage modeling tools for homebuyers, homeowners, and real estate investors. Plan smarter with detailed amortization analysis.

This tool is for planning and education only and does not constitute financial advice. Calculations are estimates based on the information you provide. Taxes, insurance, and closing costs may vary by region and lender. Always verify details with your mortgage lender or financial advisor before making decisions.

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