Flipping a house looks simple on television: buy a tired home, pour in a fresh coat of paint, and walk away with a six-figure check. In reality, the deals that survive are the ones whose numbers work on paper before the first nail is pulled. This house flipping calculator takes your After Repair Value (ARV), purchase price, rehab budget, holding time, and selling costs and tells you three things that matter most: your net profit, your return on cash (ROI), and the maximum price you should ever offer under the industry-standard 70% rule.
Adjust any field and every result updates instantly. Use it to screen a listing in minutes, compare two offers, or pressure-test a rehab budget that keeps creeping upward.
How to Use
- Enter the After Repair Value (ARV) — what the renovated home should sell for in its finished condition. Pull three or four recent comparable sales ("comps") in the same neighborhood and be conservative; an over-optimistic ARV is the single fastest way to turn a winner into a loser.
- Set the Purchase Price you are thinking of offering the seller. This is the raw acquisition cost before closing.
- Type your Rehab / Renovation Cost. Build in a 10%–20% contingency on top of your contractor's bid, because almost every flip uncovers surprises behind the drywall.
- Enter Months Held. Budget for the realistic timeline, not the fastest one. A kitchen remodel that "should" take three months can easily stretch to five once permits and weather are counted.
- Add your Monthly Holding Cost — mortgage interest, property tax, insurance, and utilities you keep paying while the home sits. The calculator multiplies this by the months held to find your total carrying cost.
- Set Selling Costs as a percentage of the sale price. Agent commission plus transfer fees, staging, and seller concessions usually land between 6% and 10%.
The result card then breaks out total holding cost, total selling cost, total cash invested, and highlights your Net Flip Profit and ROI on Cash. It also computes the 70% Rule Max Offer (MAO) — the highest price you should pay to leave yourself a safe margin.
The Flip Profit Formula
Every professional fix-and-flip model rests on one subtraction. Your net profit is everything the home is worth when finished, minus every dollar you put into or spend on it along the way:
Net Profit = ARV − Purchase Price − Rehab Cost − Holding Cost − Selling Cost
Your ROI on Cash answers the question a private lender or partner actually asks: how much did I make on the money I actually put in?
ROI = Net Profit ÷ Total Cash Invested × 100
where Total Cash Invested is your purchase price plus rehab plus holding costs. A flip that returns 20%–30% in a matter of months is strong because that annualizes to a very high number — even a 35% return over a four-month hold equals well over 100% per year.
The 70% Rule: Know Your Walk-Away Number
The 70% rule is the classic screening shortcut invented to keep investors from overpaying. It says you should offer no more than 70% of the ARV, minus the cost of repairs:
Maximum Allowable Offer (MAO) = (ARV × 0.70) − Rehab Cost
The 30% you deliberately leave on the table is meant to absorb your rehab overages, holding time, selling costs, and still leave a profit. If a property's asking price is above your MAO, the deal is usually too thin — keep shopping rather than negotiating yourself into a losing margin.
Examples
Example 1 — A solid suburban flip. You find a home with an ARV of $350,000, offer $150,000, budget $75,000 for rehab, plan a 4-month hold at $1,500/month, and estimate 7% selling costs. Total holding cost is $6,000 and selling cost is $24,500. That leaves a net profit of $94,500 on $231,000 invested — an ROI of about 40.9%. The 70% rule says your max offer is $170,000, and your $150,000 bid sits safely below it.
Example 2 — A quick, low-carry turnaround. A light cosmetic flip has an ARV of $300,000, a $150,000 purchase, $60,000 in updates, and a 0-month carrying period because you renovate while listed. Selling cost at 6% is $18,000. Net profit is $72,000 on $210,000 invested — roughly 34.3% ROI and a 24% margin on the sale.
Example 3 — A million-dollar luxury flip. A high-end ARV of $1,200,000, purchased for $600,000 with $200,000 of finishes, a 6-month hold at $3,000/month, and 6% selling costs. Net profit reaches $310,000 on $818,000 invested — about 37.9% ROI. The 70% rule caps your offer at $640,000, so the $600,000 acquisition is within discipline, but luxury homes sell slowly, which is exactly why the holding line matters.
FAQ
How do you calculate profit on a house flip?
Subtract every cost from the finished value: Net Profit = ARV − Purchase Price − Rehab Cost − Holding Cost − Selling Cost. Holding cost is your monthly carrying expense (mortgage interest, tax, insurance, utilities) times the number of months you own the home, and selling cost is usually 6%–10% of the final sale price for agent commission and closing fees.
What is a good ROI on a house flip?
Most professional flippers target a net profit of at least $25,000–$30,000 per deal and a return on cash of 20%–30% or more over a four-to-six-month hold. Because flips are short, even a 35% ROI earned in months annualizes to an outstanding yearly return. Aim for a profit margin of 10%–20%+ of the ARV after all costs.
What is the 70% rule in house flipping?
The 70% rule states that you should pay no more than 70% of a property's After Repair Value, minus the cost of repairs: MAO = (ARV × 0.70) − Rehab Cost. The remaining 30% is reserved for rehab surprises, holding costs, selling costs, and your profit. If the seller's price exceeds your MAO, the deal is typically too tight.
What costs do people forget in a flip?
The most common hidden costs are holding expenses — mortgage interest, property tax, insurance, and utilities that keep running every month the home is unfinished or unsold — plus selling costs like agent commission, staging, and seller-paid closing concessions. Budget a 10%–20% rehab contingency too, since almost every flip reveals extra work once demolition begins.
How is the After Repair Value (ARV) determined?
ARV is the price the renovated home will command, estimated from comparable recently sold homes ("comps") in the same neighborhood that are already in your target finished condition. Use three to four recent sales within a quarter mile and the last three months, and adjust for size, condition, and lot differences. A conservative ARV keeps your whole model honest.
How long does a typical house flip take?
A straightforward flip usually takes three to six months total — one to two months to buy and plan, one to four months of renovation, and one to two months to list and close. Delays from permitting, weather, contractor turnover, or a soft market can stretch this well past six months, which is why the holding-cost line in this calculator deserves real attention.
Disclaimer
This house flipping calculator is provided for informational purposes only and does not constitute financial, real estate, tax, or legal advice. All estimates depend on the accuracy of the ARV, rehab budget, timeline, and cost percentages you enter; actual results vary by market, contractor, interest rate, and resale conditions. Always verify comparable sales, obtain firm contractor bids, and consult a licensed real estate professional, accountant, or attorney before committing capital to any flip.