Before building Rental Property Calculator, we checked calculator.net's rental property calculator directly — it's a genuinely comprehensive tool covering purchase, financing, expenses, income, and even a resale projection with IRR.
Cap rate calculator, and what it doesn't tell you
Cap rate is net operating income divided by purchase price — a clean number for comparing properties, but it completely ignores how the deal is financed. A $300,000 property with a 5.96% cap rate sounds solid on paper.
Cash on cash return calculator: the number that accounts for the mortgage
Run that same property with 20% down at 7% financing, and the monthly mortgage payment ($1,596.73) actually exceeds the net operating income — the cash-on-cash return comes out negative (-2.13%), meaning you'd be losing money every month despite the "good" cap rate. Cap rate and cash-on-cash return can tell completely different stories about the same deal.
Rental property cash flow calculator, with vacancy built in
Effective income accounts for a vacancy rate rather than assuming 100% occupancy — a more realistic starting point before mortgage, tax, insurance, and maintenance costs are subtracted to get to actual monthly cash flow.
