E-commerce Fee Calculator

Methodology & data sources (2026)

Published on February 4, 2026

This page explains how the calculators model fees and profit, what assumptions are built in, and how to verify your official rates so you can trust your forecast.

1) Profit formula

Each calculator follows the same structure:

Profit = Revenue − (platform fees + payment/processing fees + other fees) − (COGS + shipping cost + other costs)
  • Revenue is usually the amount you keep (depending on whether tax is collected by the platform).
  • Fees are platform-specific (e.g., transaction/referral/final value, plus optional add-ons).
  • Costs are your costs (COGS, shipping/packaging, etc.).

2) Fee base assumptions (shipping and tax)

Many percentage fees are applied to an “order total” concept. Depending on the platform and region, this may include shipping and/or tax. That’s why calculators keep sale price, shipping charge, and tax separate — and offer toggles when platform rules differ.

If you're unsure, use the official documentation for your marketplace and payment provider, then match the calculator settings to those rules.

3) Country presets

Country presets (when available) are starting points to reduce manual work, especially for payment processing fees. Always verify your exact rate in your account because pricing can vary by product, payment method, card type, and negotiated plans.

4) Official sources

We link to official references inside the calculators and in the guides. Examples:

5) Limitations

  • Storage, advertising, returns, and disputes are often excluded by default. Add them as “Other fees/costs” to model your real unit economics.
  • Category-specific rules (Amazon/eBay) can change the effective rate. Always use your exact category schedule.

FAQ

Are these calculators “official”?

No. This site is an independent calculator. Always verify your exact fee schedule (category, country, payment method, and add-ons) on the platform’s official pages and in your account dashboard.

Why do the calculators ask for shipping and tax?

Many platforms calculate percentage fees on the total amount paid by the buyer. Depending on the platform and region, that can include shipping and/or tax. We expose toggles and separate inputs so you can match your platform’s fee base rules.

What is the basic profit formula used here?

Profit per order ≈ Revenue − (Platform fees + payment fees + other fees) − (COGS + shipping cost + other costs). You can model fixed monthly costs (like plans) as a per-order amount for more realistic margins.

How often should I update the rates?

Any time your platform updates pricing, or when you change category, country, payment provider, currency conversion settings, or advertising programs. If in doubt, confirm rates before launching a new SKU or campaign.

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