Know if it cash flows
before you buy.
The rental property cash flow calculator built for your first (or next) investment. Instantly see monthly cash flow, Cap Rate, DSCR, and multi-year projections — no spreadsheets, no guesswork.
Built by a real estate investor, for real estate investors.
Deal Snapshot
- Monthly Cash Flow
- +$847
- Cap Rate
- 7.2%
- DSCR
- 1.38
- Cash-on-Cash Return
- 11.4%
- 1% Rule
- 0.8% / 1.0%
247 Oak Ave, Columbus, OH 43215
- Purchase Price
- $220,000
- Monthly Rent
- $1,750
- Down Payment
- 25% – $55,000
- Rate (30-yr live)
- —
—30-yr fixedFreddie MacUpdated today
Features
Everything you need to analyze rental property cash flow
Whether it's your first rental or your tenth, Will It Flow gives you professional-grade analysis in a simple, intuitive interface.
Instant Cash Flow Analysis
Enter a purchase price, down payment, and rent — see your monthly cash flow, Cap Rate, DSCR, and Cash-on-Cash Return update in real time. Smart defaults handle the rest so you don't need to be an expert to get started.
Quick Adjust Sliders
Wondering what happens if you put 25% down instead of 20%? Slide to find out. Adjust purchase price, down payment, and interest rate on the fly and watch your cash flow update instantly.
Rent Comps & HUD Fair Market Rents
Get an official rent benchmark for any zip code. HUD Fair Market Rents and year-over-year trend appear on the Inputs page when you enter an address — one tap to use the estimate and set realistic rent.
Multi-Year Projections
See how your investment grows over 5 to 30 years. Visualize cash flow, equity buildup, and total return with clear charts — so you can plan your hold period with confidence.
BRRRR Analysis
Running the Buy-Rehab-Rent-Refinance-Repeat strategy? Enter your After Repair Value and see refinance projections, capital returned, new monthly cash flow, and whether you'll hit 100% capital return.
Market Intelligence
Investor opportunity score, demographics, landlord laws, eviction timeline, and neighborhood data for any zip. Unlock the full Market Intelligence card on the Outlook page with Invest to see price-to-rent, vacancy, rent growth, and more.
Stress Test Scenarios
See if your deal survives rising rates, higher vacancy, and expense spikes. One-tap scenario analysis shows how cash flow holds up under pressure — so you invest with confidence, not hope.
Multi-Tenant Support
Thinking about a duplex or triplex for your first deal? Get per-unit breakdowns with Gross Rent Multiplier, price per unit, and break-even occupancy — the metrics that matter for small multi-family.
PDF Deal Sheets
Export a professional one-page PDF summary with every metric, input, and property detail. Share it with your partner, lender, or mentor to get a second opinion on a deal.
Live Mortgage Rates
See current 30-year and 15-year fixed mortgage rates right on your home screen, along with 3-month trend data. No more switching apps to look up today's rates.
Cloud Save & Favorites
Save every analysis to the cloud, star your best deals, and load them back anytime. Attach a property photo so you can remember which house was which.
Personal Defaults
Set your preferred loan term, vacancy rate, management fee, and growth assumptions once in your profile. Every new analysis starts with your numbers — not generic ones.
How It Works
From "is this a good deal?" to knowing — in 60 seconds
No learning curve. If you can enter a price and a rent amount, you can analyze a deal.
Create your free account
Sign up in seconds with just your email. Your account keeps your analyses, defaults, and favorites synced and secure.
Enter a deal
Punch in the purchase price, down payment, rent, and a few key expenses. Smart defaults fill in the rest so you can get results fast — even if you're still learning the numbers.
See your cash flow instantly
Your KPIs update in real time — monthly cash flow, Cap Rate, DSCR, Cash-on-Cash Return. Use Quick Adjust sliders to test different scenarios on the fly.
Save, export, repeat
Save your best deals to the cloud, favorite the ones worth watching, and export professional PDF deal sheets to share with partners or lenders.
Key Metrics
The numbers every investor should know
Will It Flow calculates every metric you need using industry-standard formulas — and explains what they mean, so you can make informed decisions from day one.
Monthly Cash Flow
Income - Expenses - Mortgage$487
Positive
The number that matters most: what you actually pocket each month after vacancy, operating expenses, and debt service are paid. Positive means the property pays you; negative means you're feeding it.
Cash-on-Cash Return
Annual Cash Flow / Total Cash Invested12.3%
Excellent
How hard is your actual cash working? This measures the annual return on the money you put in — your down payment, closing costs, and repair budget. Think of it as the yield on your out-of-pocket investment.
Cap Rate
NOI / Total Acquisition Cost7.2%
Strong
Measures the property's return as if you paid all cash — useful for comparing properties regardless of how they're financed. A higher cap rate means higher income relative to price.
DSCR
Net Operating Income / Annual Debt Service1.34
Solid
Debt Service Coverage Ratio — can the property's income comfortably cover the mortgage? Lenders typically want 1.25 or higher. Below 1.0 means the rent doesn't cover the loan payment.
Break-Even Rent
Solve for rent where Cash Flow = $0$2,413
Below Market
The minimum monthly rent you'd need to break even on all expenses and debt service. If market rents are well above this number, you have a healthy cushion.
1% Rule Quick Screen
Monthly Rent / Purchase Price0.91%
Close
A fast gut-check: does the monthly rent equal at least 1% of the purchase price? It's not a definitive answer, but it's a great way to quickly filter deals worth a deeper look.
Multi-tenant properties also get: Gross Rent Multiplier, Price Per Unit, Rent Per Unit, Operating Expense Ratio, and Break-Even Occupancy. BRRRR deals include full refinance projections.
Frequently Asked Questions
Quick answers about Will It Flow and the rental property calculator.
Is Will It Flow free to use?
Yes — Will It Flow is free to sign up and use as a web app. The iOS and Android apps are also free to download when they launch.
What is DSCR and why does it matter for rental property?
DSCR stands for Debt Service Coverage Ratio. It measures whether a property's rental income covers its mortgage payments. Lenders typically require a DSCR of 1.25 or higher to approve an investment property loan. Will It Flow calculates DSCR automatically from your inputs.
Does Will It Flow work for multi-family properties?
Yes. Will It Flow includes multi-tenant support for duplexes, triplexes, and small multi-family properties. You get per-unit breakdowns, Gross Rent Multiplier, price per unit, and break-even occupancy metrics.
How is Will It Flow different from a spreadsheet?
Will It Flow updates every metric in real time as you adjust inputs, includes live mortgage rates, supports BRRRR analysis, generates PDF deal sheets, and saves all your analyses to the cloud. No formulas to build or maintain.
What metrics does the rental property calculator include?
Will It Flow calculates Monthly Cash Flow, Cap Rate, DSCR, Cash-on-Cash Return, Break-Even Rent, the 1% Rule, and multi-year projections including equity buildup and total return.
Does Will It Flow include rent comps or market data?
Yes. Will It Flow shows HUD Fair Market Rent benchmarks by zip and bedroom count on the Inputs page so you can set realistic rent with one tap. Invest subscribers get full Market Intelligence on the Outlook page: investor opportunity score, demographics, landlord laws, eviction timeline, rent growth, and neighborhood data.
Stop guessing.
Start knowing.
Analyze rental cash flow in your browser today — no install required. Free to start; optional Pro when you want PDFs, BRRRR, and deeper market intel. Native iOS and Android apps are on the way if you'd like a heads-up.
Works on desktop and mobile browsers. Create a free account and start analyzing in seconds.
Have an idea? Vote on what we build next on the community feature board.