Start with the saleable batch
Suppose ingredients cost $36 and production yields 24 saleable portions. Ingredient cost is $1.50 per serving. If two portions are discarded, the same batch spread over 22 saleable portions costs about $1.64 each. Do not reduce the recorded batch spend because some output cannot be sold.
Add the costs that move with production
For this fictional batch, 45 minutes of direct labor at a loaded $20/hour costs $15, and packaging costs $0.40 per portion. With 24 portions, pre-fee variable cost is ($36 + $15) ÷ 24 + $0.40 = $2.525 per serving. Keep precision while calculating, then round the displayed result to $2.53.
Separate percentage fees from the serving cost
At a net selling price of $8 and a 3% payment fee, the fee is $0.24. Contribution is $8 − $2.525 − $0.24 = $5.235, or about $5.24 per serving. This amount must still cover period overhead and profit. If the channel charges a fixed order fee, allocate it across the actual items in that order rather than pretending it is always a per-serving fee.
Check the denominator before comparing
Compare the same portion size, saleable yield, and net revenue basis across products. Tax collected for a tax authority is not retained sales revenue. Record whether staff meals, samples, or waste are included in the production count. A low ingredient percentage can coexist with a weak contribution once labor, packaging, and channel fees are counted.
Use your own operating data
Supplier prices, yields, labor rates, and channel fees change. KitchenMargin treats them as editable inputs rather than universal facts.