Current supported rule set
Whatnot US · USD
The calculator uses the versioned rule set whatnot-us-2026-08-11. Its official sources were last reviewed on August 16, 2026. A future rule change must create a reviewed configuration and tests instead of silently changing percentages in a page.
Calculation bases
Commission
Standard US commission is 8% of the item price after a seller-funded coupon. Coins & Money and the current Pallets promotion use 4% profiles. Buyer-paid shipping and tax are not added to the commission base.
Payment processing
Processing is 2.9% of the buyer-paid total—post-coupon item price, buyer-paid shipping, and buyer-paid tax—plus $0.30 for every separately processed transaction.
High-value orders
For qualifying high-value profiles, the category rate applies to the first $1,500 and the portion above it has 0% commission. Processing still applies to the full buyer-paid total.
Fee tax and true profit
Fee tax is applied only when a rate is supplied or reviewed; it is never guessed. True profit also subtracts seller-paid shipping, cost of goods, packaging, labor, giveaway allocation, and other entered costs.
Rounding and totals
FeeSift uses decimal arithmetic rather than binary floating-point math. For the current USD rule set, commission, processing, and fee-tax components are rounded to two decimal places with half-up rounding. Displayed totals are then built from those displayed components; FeeSift never hides a one-cent difference by changing an arbitrary line item.
estimated payout = post-coupon price − commission − processing − fee tax − seller-paid shipping
Safe auction start solver
FeeSift reuses the same versioned fee engine to test prices in exact USD cents. It expands an upper bound and then performs a deterministic binary search for the first price that breaks even, reaches the requested dollar profit, or reaches the requested profit margin.
The mathematical minimum is accepted only after the immediately previous cent has been verified to fail. A separate recommendation then rounds that passing result upward to the selected $0.50, $1, or $5 increment; it never rounds the minimum down.
Buyer-paid shipping and tax affect the processing-fee base, so the tool compares a zero lower-bound scenario with the expected and user-entered high-fee assumptions. It does not infer a buyer tax rate or address.
Reported versus expected
Calculator results are expected estimates under the selected rule version. For a completed sale, values in the marketplace report remain the authoritative reported history. FeeSift keeps those two kinds of numbers distinct rather than rewriting past transactions with today's rules.
Local report preview
CSV parsing and schema normalization
A selected CSV is handed directly to a dedicated browser worker and parsed there with a fixed comma delimiter. FeeSift checks the 25 MB limit and UTF-8 decoding before normalization; raw file content is never submitted to an application endpoint.
Headers are matched by meaning rather than column order. The mapper removes a UTF-8 BOM, trims and collapses whitespace, compares without punctuation, and applies reviewed aliases. Unknown columns remain visible for auditability instead of being discarded.
Transaction Type, Transaction Currency, and Transaction Amount are required for a basic preview. Missing order or fee-comparison fields reduce capabilities and create warnings; they do not silently invent values. Each accepted row crosses a Zod runtime validation boundary, while invalid rows remain counted and explained.
Official references
- Whatnot seller fees
- Whatnot reduced commission on high-value orders
- Whatnot Seller Weekly Orders Report
This is an estimate based on the inputs and published fee rules shown below. Actual fees can differ because of taxes, shipping, promotions, category treatment, cross-border orders, or rule changes.