Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Monthly cash flow
-$104.06
Annual cash flow
-$1,249
Cash-on-cash return
-1.39%
Cap rate
5.60%
Rent-to-price (1% test)
0.81%
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter purchase price ($).
- 2Enter down payment (%).
- 3Enter interest rate (%).
- 4Enter loan term (years).
- 5Enter monthly rent ($).
- 6Enter property tax ($/yr).
- 7Enter insurance ($/yr).
- 8Enter vacancy allowance (%).
- 9Enter management fee (%).
- 10Enter maintenance + capex (%).
- 11Read your monthly cash flow on the right — it updates as you type.
- 12Hit Share to keep the scenario or send it to someone.
About this calculator
Cash flow is what is left after the mortgage, taxes, insurance, vacancy, management, and maintenance. Most deals that look profitable on rent alone go negative once vacancy and capital expenditure reserves are honest.
Worked example
Using the values the calculator loads with:
Inputs
- Purchase price: 320000 $
- Down payment: 25 %
- Interest rate: 7 %
- Loan term: 30 years
- Monthly rent: 2600 $
- Property tax: 4200 $/yr
- Insurance: 1600 $/yr
- Vacancy allowance: 6 %
- Management fee: 8 %
- Maintenance + capex: 10 %
Results
- Monthly cash flow: -$104.06
- Annual cash flow: -$1,248.71
- Cash-on-cash return: -1.39%
- Cap rate: 5.60%
- Rent-to-price (1% test): 0.81%
What each field means
Inputs
- Purchase price ($)
- The purchase price used in the calculation, measured in $. Starts at 320000 $ so you have a working example on load.
- Down payment (%)
- The down payment used in the calculation, measured in %. Starts at 25 % so you have a working example on load. Accepted range: 0–100 %.
- Interest rate (%)
- The interest rate used in the calculation, measured in %. Starts at 7 % so you have a working example on load.
- Loan term (years)
- The loan term used in the calculation, measured in years. Starts at 30 years so you have a working example on load.
- Monthly rent ($)
- The monthly rent used in the calculation, measured in $. Starts at 2600 $ so you have a working example on load.
- Property tax ($/yr)
- The property tax used in the calculation, measured in $/yr. Starts at 4200 $/yr so you have a working example on load.
- Insurance ($/yr)
- The insurance used in the calculation, measured in $/yr. Starts at 1600 $/yr so you have a working example on load.
- Vacancy allowance (%)
- The vacancy allowance used in the calculation, measured in %. Starts at 6 % so you have a working example on load. Accepted range: 0–40 %.
- Management fee (%)
- The management fee used in the calculation, measured in %. Starts at 8 % so you have a working example on load. Accepted range: 0–20 %.
- Maintenance + capex (%)
- The maintenance + capex used in the calculation, measured in %. Starts at 10 % so you have a working example on load. Accepted range: 0–30 %.
Results
- Monthly cash flow
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Annual cash flow
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Cash-on-cash return
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Cap rate
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Rent-to-price (1% test)
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the rental property cash flow calculator work?
Cash flow is what is left after the mortgage, taxes, insurance, vacancy, management, and maintenance. Most deals that look profitable on rent alone go negative once vacancy and capital expenditure reserves are honest. The underlying maths is: Cash flow = Rent − vacancy − operating expenses − debt service. Cash-on-cash = Annual cash flow ÷ Cash invested.
What do I need to enter?
10 values: purchase price, down payment, interest rate, loan term, monthly rent, property tax, insurance, vacancy allowance, management fee, and maintenance + capex. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the monthly cash flow result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Rental Property Cash Flow Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/rental-property-cash-flow
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/rental-property-cash-flow" target="_blank" rel="noopener">Rental Property Cash Flow Calculator — RevenueLab</a> (2026).</p>
Source: [Rental Property Cash Flow Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/rental-property-cash-flow) (2026).