Why this site exists
Many sellers know their product cost but underestimate the rest of the sale. Marketplace fees, payment processing, postage, packaging, returns, and advertising costs can all reduce profit. SellerMath Tools puts those numbers in one place so a seller can make a pricing decision before money is lost.
The tools are intentionally generic. They do not assume a fixed fee for a specific marketplace because rates change and differ by country, category, account type, and promotion. Instead, the calculators ask the seller to enter the current fee settings from their own seller account.
What you can do here
- Calculate net profit after marketplace fees, shipping, packaging, ads, and return reserve.
- Estimate the lowest price needed to break even.
- Convert between margin and markup.
- Calculate the real cost of shipping and fulfillment.
- Use a practical pricing checklist before creating a listing.
Important note
The calculators are educational tools. They can help you organize pricing decisions, but they are not financial, tax, legal, or marketplace policy advice. Always verify fees, taxes, and platform rules in the official seller dashboard for your account.