Project monthly and annual rental cash flow
For rental property investors who need to forecast actual cash available after all operating expenses and debt service.
Cash Flow Calculator
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Create Free AccountWhat it does
The Cash Flow Calculator subtracts all operating expenses, debt service, and vacancy loss from gross rental income to determine your actual monthly and annual cash flow — the money that hits your account. This is the foundation metric because positive cash flow is what separates investment-grade rentals from money pits.
Unlike appreciation or equity paydown, cash flow is tangible income you can redeploy into more deals. By modeling different rent levels, expense categories, and vacancy assumptions, you can quickly identify which properties will generate immediate returns versus those requiring appreciation to break even.
Who it's for
- Buy-and-hold investors prioritizing immediate positive cash flow over appreciation plays
- Landlords managing multiple properties and needing to track each one's contribution to portfolio income
- Syndicators and passive income seekers modeling distributions to limited partners
- New investors learning how operating expenses directly reduce their take-home profits
How it works
Enter rental income
Input monthly rent, parking fees, and any other revenue streams.
Add all operating expenses
Property taxes, insurance, maintenance, utilities, vacancy reserve, management fee.
Subtract debt service
Calculate principal and interest payment; the difference is your net cash flow.
Why it matters
Forecast take-home cash after all expenses and loan payments
Compare potential properties by true monthly cash flow
Account for seasonality, vacancy, and special assessments
Decide whether a property supports your lifestyle needs
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What every calculator includes
67 Calculators
Every investment strategy — rental, flip, BRRRR, mortgage, commercial, wealth building.
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Conservative, base, and optimistic 1/2/5/10-year return modeling.
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Claude-powered analysis — strengths, risks, and actionable recommendations.
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Save unlimited reports. Revisit, compare, and track every deal you've analyzed.
Print-Ready Reports
Professional PDF reports to share with agents, lenders, and partners.
Address Auto-Fill
Enter a property address to pre-fill value, rent, and tax data automatically.
Live FRED Rates
Mortgage rate fields pre-populate with Federal Reserve interest rate data.
Investment-Grade Math
Every formula audited against professional underwriting standards.
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Frequently asked questions
What percentage should I budget for vacancy?
Conservative: 7–10% of annual rent. In strong markets: 5%. In weak markets: 10–15%. Always include it.
Should I include principal paydown as cash flow?
No — principal is forced savings, not spendable cash. Only include interest and principal separately for tax depreciation.
How do I estimate maintenance costs?
Rule of thumb: 1% of property value annually for single-family homes; 5–10% of rent for multifamily. Adjust up for older properties.
What if I have negative cash flow?
Common in high-price markets. Model whether appreciation and equity paydown offset the monthly loss and fit your long-term strategy.
Is this calculator free to use?
Yes — create a free Investor Starter account to run 1 calculator per day. No credit card required. Upgrade to Core ($49/mo) for unlimited access to all 67 calculators.
How accurate are the results?
Results are only as accurate as your inputs. The formulas use industry-standard real estate investment math. Always verify with a licensed professional before committing capital.
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