Quantity
Price the order at any quantity, including the ones nobody offered to quote
A price list gives you a handful of rates at a handful of quantities. This gives you the landed price at every quantity between them, and names the one where the tooling charge stops being the reason the price is high. Type your own figures into any field: nothing is sent anywhere and nothing is stored.
The break quantity is solved per pricing tier rather than scanned unit by unit, so a steep discount at a tier boundary cannot hide the true, smallest crossing behind a later one. Clear the order quantity and every per-unit figure prints a dash rather than a price, because an order of nothing has no unit price.
Method
What this prices, stated as plainly as the figures are
Tooling, spread over the order
The tooling charge divided by the order quantity. This is the share the quotation does not print and the only one that gets materially cheaper as the order grows.
Variable cost, with yield loss
The tier rate divided by one minus the scrap rate. Scrap is loss on units PRODUCED, not on units shipped, so every good unit carries its share of the units scrapped beside it.
Freight, spread over the shipment
One shipment per order, divided across the order. A larger order does not pay more freight; it pays the same freight over more units.
Duty, on the goods only
Charged on tooling plus variable cost, before freight. That prices an FOB shipment. A buyer on a different incoterm is on a different number, and this model says so rather than burying it.
What it cannot see
Four things this model has no way to know
A renegotiated tier
It prices the quotation as typed
Tooling shared across customers
One tool, several buyers, one bill you cannot see
A minimum that is really a schedule
Some minimums are capacity, not cost
A different incoterm
Duty is charged before freight here, which is FOB
None of these is a defect to be fixed by a better formula. They are the difference between arithmetic and a negotiation, and the page is more useful for saying which of the two it is doing.