Custo e preço

line      = grams used × price paid ÷ grams in the pack
direct    = materials + packaging × units + minutes ÷ 60 × hourly rate
total     = direct × (1 + overhead %)
per unit  = total ÷ units

fees      = price × fee % + fixed        # what the marketplace and card reader keep
margin    = (price − fees − cost) ÷ price      # a share of the price
markup    = (price − fees − cost) ÷ cost       # a share of the cost
price     = (cost + fixed) ÷ (1 − margin − fee %)   # for a target margin

• Cost of an ingredient in the batch = grams used × price paid ÷ grams bought. The price and the pack size are the maker’s own, from the invoice, so the figure is what this batch actually cost them.
• Business Development Bank of Canada, "How to set the right price for your products or services": gross margin is gross profit as a percentage of revenues; the markup is expressed as a percentage of cost of goods sold or cost of sales. So margin = (price − cost) ÷ price and markup = (price − cost) ÷ cost, and the price for a target margin is cost ÷ (1 − margin).
• Stripe, "Pricing": "2.9% + 30¢ per successful transaction for domestic cards" (United States, read 2 November 2026). A payment or marketplace fee is a share of the sale plus a fixed amount per sale, so a sale at price p keeps p × (1 − fee %) − fixed, and with margin = profit ÷ price, a target margin m needs p = (cost + fixed) ÷ (1 − m − fee %). — Fees differ by provider, country and plan, and change. The figures to use are the ones on the maker’s own statements; the calculator holds none of its own.
• Overhead is taken as a percentage of the direct costs — materials, packaging and labour — which is how a maker who knows last year’s rent, insurance and fees as a share of last year’s direct spending can carry them into one batch. — A percentage is a simplification. It is only as good as the year it was measured over, and it moves when production volume does.