Frequently Asked Questions

The calculator uses transparent financial formulas aligned with IRS guidelines (Pub 936) and CFPB rules. However, it's an estimate and may not reflect your specific situation including local market conditions, your credit score, or life changes. Always consult professionals before making decisions.

Yes. The calculator is open-source and completely free to use. No login, no ads, no data collection, no tracking. Review the methodology page for formula details and limitations.

Yes, use this as a starting point to understand rent vs. buy dynamics and see how different variables affect outcomes. But before making a real decision, speak with:

• Financial advisor (overall wealth strategy)
• Tax professional (your specific tax situation)
• Real estate agent (local market conditions)

PMI (Private Mortgage Insurance) protects the lender if you default. It's required if your down payment is less than 20%. PMI terminates automatically at three points:

1. 78% LTV: Automatic termination (no request needed)
2. 80% LTV: You can request cancellation (in writing, if payments current)
3. Loan midpoint: Auto-terminates at the halfway point (e.g., month 180 for 30-year loans)

See the methodology page for CFPB references and details.

The calculator automatically includes PMI if down payment < 20%. It applies the PMI rate (typically 0.3% to 1.5% annually) to your loan amount until one of the three termination triggers above is met. Enter your estimated PMI rate in the form.

PMI typically costs 0.3% to 1.5% of the loan amount annually, depending on your down payment %, credit score, and lender. A $300k loan with 0.55% PMI costs ~$165/month. Use a mortgage calculator or contact your lender for accurate estimates.

Yes, but with limits. Mortgage interest is deductible up to:

• $750,000 acquisition debt (after 12/15/2017, Married Filing Jointly)
• $1,000,000 acquisition debt (before 12/15/2017)

You must itemize deductions (file Schedule A) for this to benefit you. See methodology or IRS Pub 936.

Yes. You only benefit from mortgage interest deduction if your total itemized deductions exceed the standard deduction (~$13,850 single, ~$27,700 MFJ in 2024). Many homeowners now take the standard deduction. Discuss with a tax professional.

Property taxes are deductible, but capped at $10,000 total per year when combined with other state/local taxes (SALT cap). High-tax states may hit this limit quickly. This is reflected in the calculator's property tax deduction logic.

Your marginal tax rate is the tax bracket on your last dollar of income. For 2024 (MFJ):

• 10% ($0–$23,200)
• 12% ($23,200–$94,300)
• 22% ($94,300–$201,050)
• 24% ($201,050–$383,900)
• 32–37% (higher)

Higher rate = bigger tax benefit from deductions. Check your 1040 or ask a tax pro.

Break-even is the first month where buying becomes financially ahead of renting when comparing:

• Buy side: Home equity + tax benefits
• Rent side: Invested portfolio value (down payment earning returns)

If no break-even occurs by loan end, renting remained financially superior throughout your analysis period.

The calculator compounds annual appreciation monthly:

Default is 3% annual (based on long-term US average), but varies by location. Research your local market and adjust accordingly.

If you rent, your down payment + closing costs remain liquid and can be invested in stocks, bonds, etc. The calculator models this opportunity cost. This is critical for a fair comparison—it's not just rent vs. mortgage, but total wealth outcomes.

Defaults & Ranges:

• 5–6%: Conservative (mostly bonds, fixed income)
• 7% (default): Moderate (diversified index funds, ~60/40 stocks/bonds)
• 9%+: Aggressive (growth stocks, higher risk)

Use a rate reflecting your risk tolerance and expected portfolio allocation. Past performance ≠ future results.

Maintenance (default 1% annually) estimates repair and upkeep:

• Roof, HVAC, plumbing, electrical
• Painting, flooring, appliances
• Landscaping, exterior repairs

Actual costs vary by home age, condition, and climate. Use 1% for modern homes, 1.5%+ for older homes. This is a rough estimate.

Closing costs on purchase are included (default 2%), but realtor fees on sale (~5–6%) are not modeled. For a complete picture of breaking even, add realtor fees manually. This is why break-even typically takes 5–7+ years.

This calculator only models fixed-rate mortgages with fixed payments. ARMs (Adjustable Rate Mortgages), interest-only loans, and balloon mortgages are not supported. For those, consult your lender or a professional.

No. The calculator assumes you stay in the home for the full loan term or analysis period. In reality, people move for jobs, schools, family reasons, etc. Factor in your personal timeline.

Those are partially captured in maintenance (1% default). For a detailed breakdown, model separately or adjust maintenance % upward. Renters also pay utilities, so this may wash out in comparison.

Add special assessments to maintenance %. Use the HOA fee field for condo/HOA monthly costs. Flood insurance should be added to homeowners insurance if in a flood zone.

Yes. This calculator uses US tax law (IRS Pub 936), CFPB PMI rules, and US market assumptions (appreciation, interest rates, investment returns). Adapt for other countries.

Step 1: Enter your inputs (home price, down payment %, interest rate, taxes, insurance, rent, etc.).
Step 2: Results update in real-time—see monthly costs, break-even month, and final comparison.
Step 3: Download CSV or adjust inputs to run scenarios.

Yes! Try different interest rates, down payments, or rent amounts to see the impact. E.g., "What if rates drop 1%?" or "What if I put down 25% instead of 20%?" Export each CSV and compare in a spreadsheet.

Yes. Click '📥 Export CSV' to download the full monthly schedule with all calculations (mortgage, interest, principal, PMI, taxes, home value, equity, rent, portfolio, etc.). Open in Excel/Sheets for further analysis.

Defaults are based on 2024 US market averages:

• Home: $400k, 20% down, 30-year, 6.5% rate
• Taxes: 1.1% annual property tax
• Insurance: $150/month, 1% maintenance
• Rent: $2,500/month, 3% annual growth
• Investment: 7% annual return, 24% tax rate

Click '↻ Reset' to restore defaults anytime.