Check any flip before you buy it. Set where you are buying and where you are selling, and Kickflip returns your profit in dollars and your margin as a percentage — after commission, payment processing, promotions, shipping and sales tax.
Fee estimates use the primary tier rate from each platform's public schedule. Tiered pricing, promotion rates, and buyer-fee ranges vary — always confirm current rates with the platform before listing.
Retail arbitrage looks like simple subtraction: buy at one price, sell at a higher one, keep the difference. In practice the difference is where the money disappears. A flip carries costs on both sides of the trade, and most of them are invisible on the listing page.
On the buying side you pay:
On the selling side the marketplace takes:
Kickflip mirrors both stacks side by side so you can see exactly where the spread went, rather than discovering it in your payout.
The most useful way to use this tool is in reverse. Turn on target margin, enter the return you need, and it solves for the sale price required to get there — or, when you are bidding on an auction, the maximum you can pay and still hit your number. That converts a gut call at a thrift store or in the last thirty seconds of an auction into a fixed walk-away price.
Running a listing through a calculator one at a time is fine for a big purchase and impractical for sourcing at volume. The Kickflip browser extension scans the product page you are already on, pulls comparable sold and active prices from other marketplaces, and scores the arbitrage opportunity without you leaving the page.
Retail arbitrage is buying an item at one price — from a store, a clearance rack, or a marketplace listing — and reselling it somewhere the same item sells for more. The profit is the spread between the two prices, minus every fee, shipping cost and tax involved in the round trip.
Profit is the sale price minus the selling platform's commission and payment processing, minus any advertising or promotion cost, minus the shipping you pay, minus what the item cost you including inbound shipping and the sales tax you paid at the source. Margin is that profit expressed as a percentage — either of your total cost (ROI) or of the sale price.
There is no single correct target; it depends on your category, how fast the item sells, and how much cash you have tied up while it sits. What matters is picking a target and testing every purchase against it before you buy. Kickflip's target margin mode works backwards from the return you want and tells you the maximum price you can pay.
The three most commonly missed are the sales tax paid on the original purchase, platform advertising costs such as eBay Promoted Listings, and the fact that most marketplaces charge their commission on the item price plus buyer-paid shipping plus tax rather than on the item price alone.
Buying and reselling legitimately acquired goods is generally permitted in the US under the first-sale doctrine, though individual marketplaces set their own selling policies and some brands and categories are restricted. Tax treatment of resale income varies — check your local rules or a professional. This tool estimates margin, not legal or tax advice.