Run the numbers on any real estate deal in seconds
The calculators serious property investors actually use — from mortgage payments and cap rates to Airbnb income and the 70% flip rule. Free, instant, and private.
Choose a calculator
Every tool updates instantly as you type and explains the math beneath it.
Mortgage Calculator
Estimate your monthly payment including principal, interest, taxes, insurance and HOA.
Open calculator AnalysisCap Rate Calculator
Measure a property’s unleveraged annual return from net operating income.
Open calculator AnalysisCash-on-Cash Return
Return on the actual cash you invest, after financing and all expenses.
Open calculator AnalysisRental Yield Calculator
Gross and net rental yield to quickly screen income properties.
Open calculator AnalysisProperty ROI Calculator
Total annual return combining cash flow and appreciation on invested capital.
Open calculator StrategyFix & Flip Profit
Project profit and the 70% rule max offer for a house flip.
Open calculator StrategyRent vs. Buy
Compare the total cost of buying vs. renting over your expected time horizon.
Open calculator Short-Term RentalAirbnb / STR Estimator
Project short-term rental revenue and net cash flow from nightly rate and occupancy.
Open calculator StrategyBRRRR Calculator
Buy, Rehab, Rent, Refinance, Repeat — see how much cash you pull back out after the refi.
Open calculator FinancingRefinance Calculator
Compare your current loan to a new one, including cash-out, and find your break-even point.
Open calculator ClosingProperty Tax Proration
Split the annual property tax fairly between buyer and seller based on the closing date.
Open calculator Strategy1031 Exchange Calculator
Estimate the capital gains tax you can defer with a like-kind exchange — and your deadlines.
Open calculator FinancingDSCR Loan Calculator
Debt Service Coverage Ratio — the metric investor lenders use to qualify a rental with no income docs.
Open calculator StrategyWholesale / Assignment Fee
Find your max allowable offer and the assignment fee spread you can lock into a wholesale deal.
Open calculator ClosingSeller Net Proceeds
See exactly what you’ll walk away with after paying off the loan and all selling costs.
Open calculator AnalysisDepreciation Calculator
Estimate your annual depreciation deduction and the tax it shelters on a rental property.
Open calculator StrategyBRRRR Seasoning Timeline
Plan when you can refinance, and how much equity and cash-out you’ll have at the seasoning date.
Open calculator FinancingAmortization Schedule
See your loan balance melt away year by year, and how much of every payment goes to interest vs. principal.
Open calculator AnalysisCost Segregation Estimator
Estimate the first-year tax savings from accelerating depreciation with a cost-segregation study.
Open calculator FinancingHELOC / Second-Position
See how much equity you can tap with a HELOC or second mortgage, and the interest-only payment.
Open calculator StrategySyndication Waterfall
Split profits between limited partners and the sponsor using a preferred return plus a promote.
Open calculator FinancingHome Affordability Calculator
Estimate the home price you can afford based on income, debts, down payment and rate.
Open calculator FinancingPMI Removal Calculator
Find out when you can drop private mortgage insurance and how much you’ll save.
Open calculator AnalysisGross Rent Multiplier Calculator
A fast value screen: how many years of gross rent it takes to equal the price.
Open calculator Analysis1% & 50% Rule Calculator
Two classic rental screens: does rent clear 1% of price, and does the 50% rule leave cash flow?
Open calculatorWhy investors use these numbers
Smart real estate investing comes down to a handful of metrics. Cap rate and cash-on-cash return tell you whether a rental produces enough income. ROI captures the full picture — cash flow, appreciation, and loan paydown together. For flips, the 70% rule keeps you from overpaying, and for short-term rentals, occupancy and nightly rate drive everything.
These calculators give you fast, honest answers before you ever make an offer. Bookmark the ones you use most, and always confirm assumptions like rents, expenses, and comparable sales with local data.
Guides & Insights
Plain-English breakdowns of the numbers behind real estate deals — with the calculators to run them yourself.
What Is a Good Cap Rate for Rental Property?
The honest answer is "it depends" — but here are the real 2026 ranges, and how to know if a deal is actually good.
StrategyThe 70% Rule for House Flipping, Explained
The one-line formula that keeps flippers from overpaying — plus when to bend it and when it will burn you.
StrategyThe BRRRR Method: A Step-by-Step Guide
Buy, Rehab, Rent, Refinance, Repeat — how to recycle the same down payment into a whole portfolio, and where it goes wrong.
FinancingHow Much House Can You Really Afford?
The 28/36 rule, what lenders actually check, and why the number they approve isn’t the number you should spend.
FinancingHow to Get Rid of PMI (and Stop Overpaying)
The 80% request, the 78% automatic drop, and the appraisal trick that can kill PMI years early.
AnalysisWhat Is a Good Gross Rent Multiplier?
The fastest screen in rental investing — the typical 4–12 ranges, and why the national average is useless.
AnalysisThe 1% Rule and 50% Rule for Rentals
Two ten-second gut-checks every landlord quotes — how they work, and why they fail in half the country.
FinancingHow Mortgage Payments Actually Work
PITI, amortization, and why your early payments are almost all interest — explained in plain English.
FinancingWhen Does Refinancing Make Sense?
Forget the old 1% rule — in 2026 the only number that matters is your break-even point.
FinancingWhat Is a DSCR Loan? A Guide for Investors
The loan that qualifies your property instead of you — how DSCR works and what lenders want in 2026.
StrategyCost Segregation Explained (and Why 2026 Is Huge)
The tax strategy that front-loads depreciation — now supercharged by permanent 100% bonus depreciation.
StrategyWhat Is a 1031 Exchange? The 45/180-Day Rules
How to sell an investment property and defer the capital gains tax entirely — if you hit two unforgiving deadlines.
Closing & STRHow to Calculate Airbnb Income (ADR, Occupancy, RevPAR)
The three numbers that predict what a short-term rental will actually earn — and the 2026 benchmarks to judge them against.
About REI Calc
REI Calc is a free suite of 25 real estate investment calculators built for the people who actually run the numbers on deals — landlords, house flippers, short-term rental hosts, wholesalers, and buy-and-hold investors.
Why we built it
Most real estate math lives in messy spreadsheets or behind sign-up walls. We wanted a single, fast, private place to answer the questions investors ask before every deal: What's the cap rate? Does this cash-flow? Is the flip worth it at this price? How much equity can I pull with a HELOC? Every calculator gives you an instant answer and explains the formula beneath it, so you learn the math as you use it.
Who's behind it
REI Calc is run by a hands-on property investor based in Springfield, Missouri, who manages short-term and long-term rentals. The tools reflect real workflows used to evaluate, finance, and operate income properties — not textbook theory. As the site grows we're adding guides, worked examples, and market insights to help newer investors make confident, numbers-first decisions.
How it works
Everything runs in your browser. You type in your numbers, the calculator updates instantly, and nothing you enter is stored or sent anywhere. There's no account to create and no cost — the site is supported by advertising so the tools can stay free for everyone.
A note on accuracy
REI Calc provides estimates for educational purposes only and does not constitute financial, tax, legal, or investment advice. Formulas follow standard industry conventions, but real-world costs, taxes, rates, and returns vary. Always confirm your assumptions and consult a qualified professional before making a real estate decision.
Questions or feedback? Get in touch — we read every message.
Contact us
Have a question, spotted a bug, or want to suggest a calculator we're missing? We'd love to hear from you.
The fastest way to reach us is by email:
Set up this inbox on your domain ([email protected]) so messages reach you — most registrars and email hosts let you add it in a few minutes.
What to include
- Feature requests — tell us which calculator you'd like added and how you'd use it.
- Corrections — if a formula or result looks off, send the inputs you used so we can reproduce it.
- Partnerships & advertising — reach out if you'd like to work with us.
We typically reply within a couple of business days.
Privacy Policy
Last updated: July 2026. This policy explains what information REI Calc collects, how it's used, and the choices you have.
The short version
The numbers you type into our calculators are processed entirely in your browser. We do not store, transmit, or have access to the figures you enter. We do use standard web analytics and advertising services, which are described below.
Information we collect
Calculator inputs: None are collected. All calculations run locally on your device and are never sent to our servers.
Usage data: Like most websites, we may collect anonymous, aggregated information such as pages visited, browser type, device type, referring site, and general location (country/region). This helps us understand which tools are useful and improve the site.
Cookies and similar technologies: We and our partners use cookies and similar technologies to remember preferences (such as light/dark mode), measure traffic, and serve advertising.
Advertising and third parties
This site is supported by advertising. We plan to use third-party ad networks, including Google AdSense. Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this and other websites.
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- For more on how Google uses data, see Google's policy.
Analytics
We may use privacy-respecting analytics services to measure aggregate traffic. These services do not identify you personally.
Your choices
You can disable cookies in your browser settings, though some features (like remembering dark mode) may not work as expected. You can opt out of personalized ads using the links above.
Children's privacy
This site is intended for adults and is not directed at children under 13. We do not knowingly collect personal information from children.
Data for users in the EU, UK, and California
Depending on your location, you may have rights under laws such as the GDPR or CCPA, including the right to access or delete personal data and to opt out of the sale or sharing of personal information. Because we do not collect personally identifiable information directly, most requests relate to cookies set by our advertising and analytics partners, which you can manage using the opt-out links above. Contact us with any questions.
Changes to this policy
We may update this policy from time to time. Material changes will be reflected by the "last updated" date above.
Contact
Questions about this policy? Contact us here.