Best Free Real Estate Calculators Compared
We tested and compared the best free real estate calculators available in 2026. Here are the ones that actually get the math right and are worth bookmarking.
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
- Cap rate: 5.76%
- Cash-on-cash: 4.2%
- Annual NOI: $20,160
- Cap rate, cash flow, ROI, BRRRR, mortgage in one place
- No signup required
- Handles vacancy and expense ratios correctly
- Mobile-friendly
- Try it here 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
- 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
Results should come out to approximately:
Our Rankings
Tier 1: Accurate + Comprehensive
RealEstateStackHub Free Calculators ✅Tier 2: Good But Limited
Zillow Mortgage Calculator ✓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.