Who Built This

A Reseller Who Got Tired of Googling

FeeCalc was built by a full-time reseller who sells across multiple platforms. The problem was simple: every time you need to price something on a different marketplace, you're Googling "[platform name] seller fees" and doing math on a napkin.

That gets old fast when you sell on eBay, TCGPlayer, Amazon, Etsy, Mercari, Poshmark, StockX, Depop, Whatnot, Facebook Marketplace, and Walmart.

So he built a calculator that handles all of them in one place. That's FeeCalc.

What You Get

All calculations run locally in your browser. No servers, no accounts, no tracking. Open the extension, punch in your numbers, and see exactly what each platform takes and what you keep.

Why Free?

Because fee calculators shouldn't cost money. You're already paying platform fees — you shouldn't have to pay to find out what they are.

The extension includes affiliate links to the selling platforms it covers. When you sign up for a platform through one of those links, a small commission comes back this way. That covers hosting costs. The fee math is never affected by affiliate partnerships — the numbers come from official platform documentation, period.

Kept Current

Platforms change their fee structures constantly. eBay tweaks final value fees. Mercari adjusts seller rates. StockX updates transaction fees. When that happens, the calculator gets updated too. All rates reflect current 2026 fee schedules pulled from each platform's official seller documentation.

Get in Touch

Found a bug? Fee rate out of date? Want to request a platform? Just say hi? Reach out.