Best Free Real Estate Calculators Compared

# Best Free Real Estate Calculators Compared A good calculator can save you from a bad deal. We tested 15 free real estate calculators for accuracy, ease of use, and completeness. Here's what we found. ## What We Tested We ran each calculator against a standardized test property: - Purchase price: $350,000 - Down payment: 25% - Gross rent: $2,800/month - Vacancy: 8% - Expenses: 35% of gross rent - Mortgage rate: 7.0%, 30-year fixed Results should come out to approximately: - Cap rate: 5.76% - Cash-on-cash: 4.2% - Annual NOI: $20,160 ## Our Rankings ### Tier 1: Accurate + Comprehensive **RealEstateStackHub Free Calculators** ✅ - Cap rate, cash flow, ROI, BRRRR, mortgage in one place - No signup required - Handles vacancy and expense ratios correctly - Mobile-friendly - [Try it here](/tools) **BiggerPockets Calculator (Free Tier)** ✅ - Strong rental property and BRRRR calculators - Requires free account creation - Excellent for generating shareable reports - 5 analyses/month on free tier ### Tier 2: Good But Limited **Zillow Mortgage Calculator** ✓ - Accurate mortgage payment math - Doesn't factor in expenses, vacancy, or NOI - Good as a quick monthly payment check **Bankrate Rental Property Calculator** ✓ - Covers cash flow basics - Expense inputs are limited (no vacancy rate control) - Ignores DSCR ### Tier 3: Avoid Multiple spreadsheet tools found on YouTube and Reddit contained errors in expense ratio calculations that would cause investors to overestimate cash flow by 15–25%. ## The Bottom Line For quick deals: Use our free cap rate and cash flow calculators at RealEstateStackHub — no account needed. For deep analysis: BiggerPockets' calculator is worth the free account for its report generation. For mortgage math: Bankrate or our mortgage calculator get the payment calculation right. Never rely on a calculator that doesn't account for vacancy, maintenance, and property management as separate expense line items. Those "optimistic" calculators are how people buy bad deals.