Methodology
Every number on this site is an estimate of a published fee rule, not a quote from a platform. Here is exactly how we build the estimate, and where it can be wrong.
Sources
We use primary sources where they are available:
- eBay Seller Center fee pages, category tables, and Store selling fee documentation.
- Amazon Seller Central referral and FBA fee documentation, including the 2026 US fee changes and the fuel and logistics surcharge announcement.
- Etsy’s Fees & Payments Policy and Etsy Payments processing rates.
- Shopify’s pricing page, Shopify Payments rates, and third-party transaction fee documentation.
When a primary page is gated or changes without a public changelog, we cross-check with a second source and label the result as an estimate.
Default assumptions
| Assumption | Default |
|---|---|
| Country | United States |
| Currency | USD |
| Order size | One order; quantity only where the platform charges per item |
| Sales tax / VAT | Excluded from revenue; included in the eBay fee base when entered |
| Shopify billing | Annual plan pricing |
| Amazon fulfillment | User-entered fee, plus the 3.5% 2026 surcharge |
| Advertising | Excluded unless the user enters a rate |
How each calculator models fees
eBay
Final value fee = category rate × (item price + buyer-paid shipping + sales tax), applied to the portion up to the category cap, then 2.35% above the cap. Store subscribers use the discounted rate and the Store cap. A per-order fee of $0.40 ($0.30 for orders of $10 or less) is added; sneakers at $150+ have no per-order fee. Promoted Listings is charged on the total sale amount when entered.
Amazon FBA
Referral fee = category rate × sale price, with a $0.30 minimum. Media categories add a $1.80 closing fee. FBA fulfillment is user-entered and multiplied by 1.035 for the 2026 fuel and logistics surcharge. Storage and inbound are per-unit inputs. The Professional plan is allocated across monthly units; the Individual plan adds $0.99 per item. Advertising is optional.
Etsy
Listing fee = $0.20 × quantity. Transaction fee = 6.5% × (item price + shipping). Payment processing = 3% × total + $0.25 (US). Offsite Ads = selected rate × total. Etsy Plus and sales tax are excluded.
Shopify
Processing = orders × (average order value × plan rate + plan fixed fee). If a third-party gateway is selected, the plan’s surcharge replaces the Shopify Payments rate and the gateway’s own percentage and fixed fee are added separately. The monthly plan and apps are deducted from monthly profit.
What the estimates do not include
- Account-specific promotions, negotiated rates, or grandfathered pricing.
- Returns, refunds, chargebacks, and refund administration fees.
- Currency conversion, international fees, and VAT.
- Inbound freight, prep-center fees, and storage overage.
- Ad spend unless you enter it.
- Taxes on your profit.
Update cadence
Core fee tables are reviewed monthly. A page’s review date is shown near the title. When a platform announces a change, we update the affected calculator and guide, and note the change where practical. If you spot a discrepancy, email [email protected] with the platform, category, date, and a screenshot or link. We will verify and correct it.
Why we publish the method
A calculator is only useful if you can audit it. Publishing the formula lets you check our work against your seller dashboard, and it makes the estimate more honest: a range with visible assumptions is better than a single number with no explanation.
Last updated: November 2026.