Free tools
Every calculator here runs the same deterministic math as the Mortar Chrome extension, with real per-state property tax and insurance instead of a national average. Free, no signup, and each one shows its work.
Rental property calculator
The full screen: cap rate, cash flow, cash-on-cash and a verdict, with real per-state taxes and insurance.
Cap rate calculator
Net operating income over price, computed with real per-state property tax and insurance.
Cash-on-cash return calculator
What the cash you actually put in earns, with your own down payment, rate and term.
Rental cash flow calculator
Monthly rent minus mortgage and every honest expense line, including reserves.
Max offer calculator
Work backwards: the highest price at which a deal still clears your cash flow and return targets.
Screening a lot of listings?
The Mortar Chrome extension runs this exact analysis automatically on any Zillow listing. No typing. Free to start.
All figures are estimates for screening deals, not financial advice or an appraisal. For the reasoning behind each number, read the Mortar blog.