car flipping calculator | true profit, max offer, SE tax
Unlicensed flippers pay sales tax when they buy the car, and the IRS takes 15.3% self-employment tax on 92.35% of the profit.
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- Enter your details in the free version below.
- See your result right away on this page.
- Need more? The full version adds what is listed under "What you get".
What you get: every car saved in a garage, days held from dates, rolling 12-month sale count with the next date a sale stays under your line, year profit, cash in unsold cars, CSV, backup, deal sheets.
Unlicensed flippers pay sales tax when they buy the car, and the IRS takes 15.3% self-employment tax on 92.35% of the profit. In Florida, 3 cars bought or sold in any 12 months presumes you are a dealer. 8 inputs and 12 formulas.
Example (made-up car): bought at $6,200, sold at $9,500. The $3,300 spread loses $2,260.97 to sales tax, fees, reconditioning, 21 holding days and 15.3% self-employment tax, so you keep $1,039.03, and paying $6,200 instead of the $5,693.57 max offer overpaid $506.43.
Free flip calculators stop at sale price minus buy price and repairs. This one adds the sales tax you pay at purchase without a dealer resale exemption, the days the car sits and the IRS self-employment tax, then tells you the most to offer before you bid.
Your numbers
Your result
| Sales tax paid at purchase | - |
| Holding cost for the days held | - |
| All-in cost of the car | - |
| Spread (sale price minus purchase price) | - |
| Profit before tax | - |
| Self-employment tax (15.3% of 92.35%) | - |
| True profit after SE tax | - |
| Spread lost to tax, fees and holding | - |
| Return on all-in cost | - |
| True profit per day held | - |
| Max offer for your target profit | - |
| Overpaid above the max offer | - |
Everything updates as you type. Nothing is uploaded. This runs in your browser.
Why the spread lies: the IRS self-employment tax is 15.3% (12.4% Social Security + 2.9% Medicare) on 92.35% of net earnings, owed once your year's net earnings reach $400 (irs.gov, read 2026-11-15). Federal and state income tax are not included.
Count your cars: in Florida, buying, selling or offering three or more motor vehicles in any 12-month period presumes you are a dealer (Florida Statutes 320.27(1)(c), flsenate.gov, read 2026-11-15). Other states set their own rules.
Full version — $29 once: the Excel workbook with a 20-car flip log that totals true profit and SE tax for the year and counts your cars in the last 12 months against your state's dealer count. Get the workbook