50% Rule Calculator

The 50% rule says that over time, about half of gross rent goes to operating costs — taxes, insurance, repairs, vacancy, turnover — before the mortgage. Enter rent and your monthly principal & interest and it estimates the cash flow that remains.

Inputs

Monthly rent, all units ($)Monthly mortgage payment, P&I only ($)

Result

Estimated operating costs (50%)–

Estimated monthly cash flow–

This is a screening rule of thumb, not underwriting. Before an offer, run the full month-by-month math in the house hacking calculator or the 6-step checklist.

More free VanToVault tools: House Hacking Calculator · Rent vs. Buy · BRRRR · FIRE Projector · Rent Comps · Full cash-flow walkthrough

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