How to find your maximum ad cost per sale
Find the most you can spend on ads for one dropshipping sale after supplier cost, shipping, and fees.
Start from what the customer pays
Add the product price and any shipping you charge. That customer total is the money you have to work with. Subtract the supplier’s product cost and the shipping you pay the carrier or the warehouse.
Then subtract the card fee and any platform fee you actually pay. What remains is the contribution before ads. That amount is the most the sale can spend on advertising without going negative.
Treat break-even as a ceiling, not a target
Break-even ROAS is the customer total divided by the contribution, when the contribution is still positive. An ad that returns less than that multiple does not cover the costs you entered.
A target you want to keep, and a refund reserve you choose to set aside, both shrink the cost per sale you can afford. The profit calculator on this site asks for those amounts. It does not invent a reserve or a “good” ROAS.
Write the number down before the first ad
Put your quote into the free profit calculator linked on this page. Leave ad cost blank to see the ceiling. Enter a cost per sale only when you have one from a test, or when you want to see what that cost would leave.
Save the quote in a launch workspace when you want the number next to the supplier note and the campaign draft. A free account keeps 3 workspaces. Pro raises that cap. The calculator itself stays free and does not start checkout.
Questions
What if the contribution is zero or negative?
There is no ad budget that makes the order profitable. Change the price, the supplier cost, or the shipping before you buy traffic.
Should I use my target cost per sale or the break-even cost?
Know both. Break-even is the point where the sale stops covering the costs you entered. A target remainder is what you want left after ads. Spend above break-even and the order loses money on these inputs.
Does Dropship Scout store the quote?
The public calculator does not. A launch workspace does, after you create an account. Pro does not change the math. It raises the number of workspaces you can save.