Rental Property Calculator
This calculator provides multiple analysis modes for rental property investments including Net Operating Income (NOI), capitalization rate (cap rate), mortgage payments, annual debt service, cash flow before tax, and cash-on-cash return. Use the mortgage mode to model financed purchases and the cap-rate mode for quick underwriting.
Values are estimates for screening and scenario planning. Always reconcile to official loan documents, local tax statements, insurance quotes, and a qualified accountant or attorney for tax and compliance advice.
Includes mortgage amortization, annual debt service, cash flow before tax and cash-on-cash return. Default method for financed purchases.
Inputs
Results
Monthly Mortgage Payment
-$2.50
Annual Debt Service
-$30.00
Net Operating Income (NOI)
$14,880.00
Cash Flow Before Tax (annual)
$14,910.00
Total Cash Invested
$63,000.00
Cash-on-Cash Return
2366.67%
| Output | Value | Unit |
|---|---|---|
| Monthly Mortgage Payment | -$2.50 | USD |
| Annual Debt Service | -$30.00 | USD |
| Net Operating Income (NOI) | $14,880.00 | USD |
| Cash Flow Before Tax (annual) | $14,910.00 | USD |
| Total Cash Invested | $63,000.00 | USD |
| Cash-on-Cash Return | 2366.67% | % |
Visualization
Methodology
Calculations follow standard real estate underwriting conventions: annualizing monthly income, subtracting vacancy to obtain effective gross income, and subtracting operating expenses to derive NOI.
Mortgage amortization uses a fixed-rate annuity formula to compute level monthly payments and annual debt service. Cash-on-cash return divides pre-tax annual cash flow by total cash invested (down payment, closing costs, rehab).
For trust and reproducibility, engineering and accuracy practices align with industry good practices and controls recommended by standards bodies. This tool recommends verification of inputs and periodic calibration against actual performance data; see citations for relevant standards and guidance.
Further resources
External guidance
Expert Q&A
How accurate are results?
Results are estimates based on the inputs and the formulas shown. Accuracy depends on input quality. This tool does not replace lender underwriting, appraisals, inspections, or tax advice. Validate results against actual loan offers, tax bills, and insurance quotes.
Should I include principal paydown in returns?
This calculator shows pre-tax cash flow and commonly used metrics (NOI, cap rate, cash-on-cash). Principal paydown and tax effects increase total investor return but are excluded from the core cash-on-cash calculation. Use the outputs as building blocks to model total return separately.
Are regulatory or safety standards applied?
This tool references recognized standards and recommends that users follow applicable regulatory, safety, and data-handling guidance (see citations). It does not automate compliance checks for local building, safety, or landlord-tenant laws.
What are typical calibration limits?
Inputs like vacancy rate, management fees, and repair reserves should be based on local market data and historical performance. If inputs are outside reasonable bounds (for example, negative rents or vacancy far above 100 percent), results may be invalid. Use sensitivity testing to understand outcome ranges.
Sources & citations
- NIST - Framework and guidance for measurement and reporting best practices — https://www.nist.gov
- ISO - International Organization for Standardization (quality and risk management guidance) — https://www.iso.org
- IEEE - Standards for software and system engineering best practices — https://www.ieee.org
- OSHA - Occupational Safety and Health Administration (safety guidance for property work) — https://www.osha.gov