FeeStackBase

Methodology

Last updated: July 19, 2026

Estimate only — not your Seller Hub, Seller Central Fee Preview, or Etsy payout screen. Confirm rates in the platform before you list or restock.

How FeeStackBase turns a sale price into a fee stack. Defaults are US public-rate starting points with an “as of” stamp. Every percent and flat fee can be overridden when your account shows a Store discount, category exception, UK marketplace table, or country-specific processing rate.

Current stamp: 2026-07-19. US public seller fee starting points. Override any % when Seller Hub / Seller Central / Etsy payments disagree. Not official platform software.

Rate tables live in static JSON under src/lib/fsb/rates/. Update the JSON, keep the formula code. Arithmetic runs in a browser Web Worker when available.

eBay (US business-style defaults)

  • Most categories final value fee ~13.6% on total sale (item + buyer-paid shipping) up to $7,500, then 2.35%
  • Per-order fee $0.30 if total ≤ $10, else $0.40 (managed payments line — not a second PayPal cut)
  • Optional promoted listings % and international buyer toggle (+1.65% in our table)
  • Category stubs include trading cards and other common overrides — Hub still wins when your Store rate differs
  • Reverse list-price hint on profit pages: solve for a price that targets profit with ads/intl off

Start: eBay fee calculator. Legacy PayPal wording: PayPal note page — do not double-count processing for typical US managed payments.

Amazon FBA (planning)

  • Default referral 15% — override by category when you know Hub’s rate
  • Fulfillment from an editable stub (US default $3.86; UK page uses a separate stub ~$3.22) — paste Fee Preview / Seller Central when you have a size tier
  • Storage / other / ads optional lines; COGS and inbound on profit-oriented pages
  • USA and UK geo pages share the engine with marketplace-shaped defaults — not live Fee Preview

Start: Amazon FBA calculator. Fulfillment zoom: fulfillment fee calculator.

Etsy (US-oriented defaults)

  • Listing $0.20 per sold-unit model line
  • Transaction 6.5% on item + shipping + gift wrap
  • Processing 3% + $0.25 — confirm for your country in Etsy
  • Offsite Ads optional when attributed
  • Price calculator reverse hint: list price for a target profit with Offsite off and $0 shipping in the reverse math

Start: Etsy fee calculator. Reverse: Etsy price calculator.

Shopify (footnote)

  • Default processing style 2.9% + $0.30 (Basic-plan shaped) — override to match your plan
  • Optional platform / app % (default 0)
  • Not Shopify Billing, tax, or a marketplace FVF stack

One page only: Shopify fee calculator.

What we do not claim

  • No live API to seller accounts or Fee Preview size tiers
  • No tax, VAT, or income advice
  • No PPC strategy beyond the optional ads % you type
  • No guarantee your payout matches after refunds, holds, coupons, or account-level adjustments

Wrong default or a stack that disagrees with Hub? Contact with the URL and inputs.