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Rental Income Calculator

Project monthly rental income and cash flow on any property. Enter rent, vacancy, expenses, and financing to see what actually lands in your bank each month.

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Global Property Details

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$
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Property
Shared Financing

Applies to this tab. Down payment, rate, and term drive the mortgage.

%
= $50,000 down
%
= $6,000 closing
%
≈ $1,264 / mo P&I
yr
≈ $255,089 interest over 30 yr
Teaser metric, free preview
Monthly Cash Flow
$242
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  • Deal score (0–100)
  • Monthly cash flow
  • Cash-on-cash return
  • Cap rate & DSCR
  • 1%, 50%, rent/PITI rules
  • Break-even occupancy
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LTR inputs
$
%
1 to 4 unit residential. Larger multifamily coming later.
$
Operating expenses
%
%
%
Total monthly OpEx: $209
Custom expenses

No custom expenses yet. Add anything specific to this deal, lawn care, permits, pest, etc.

Adds $0/mo equivalent.

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How a rental income calculator actually works

Most "rental income" tools just multiply rent by twelve. That misses the entire story. Real rental income, the kind that ends up in your bank account, only shows up after vacancy, operating expenses, and debt service are subtracted from gross rent.

The cash flow formula

Net rental income = Gross rent − Vacancy − Operating expenses − Debt service.

Gross rent is what's on the lease. Vacancy is the percentage of the year the unit sits empty. Operating expenses include taxes, insurance, HOA, property management, maintenance, and capex reserves. Debt service is the principal-and-interest portion of your mortgage payment.

Vacancy is not optional

Even in tight markets, count on 5–8% vacancy. Tenants leave, turnover takes 2–4 weeks for cleaning, painting, and showings, and the next tenant doesn't always sign in week one. Skipping vacancy is the most common reason "great deals" turn into break-even ones.

The operating-expense floor

  • Property management: 8–10% of collected rent, even if you self-manage today.
  • Maintenance: 5–10% of rent depending on age and condition.
  • Capex reserves: 5–10% of rent for major systems (roof, HVAC, water heater).
  • Taxes + insurance + HOA: Fixed monthly cost, look up the real numbers, don't guess.

Common mistakes

  • Counting the security deposit as income (it isn't).
  • Modeling rent at the top of the comp range instead of the median.
  • Ignoring annual rent increases that compound over a 5-year hold.
  • Forgetting utilities you cover (water, sewer, trash, common-area electric).

Glossary

  • Gross rent: What the lease states. Top-line.
  • Vacancy: Percentage of bookable months the unit sits empty.
  • NOI: Net Operating Income. Rent minus operating expenses (excluding debt service).
  • Cash flow: NOI minus debt service. What lands in your account each month.
  • DSCR: Debt Service Coverage Ratio. NOI ÷ annual mortgage payment.

Frequently asked questions

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Estimates only, based on the inputs you provide and third-party data. Not investment, tax, accounting, or legal advice. See our full disclaimer.