The shortest reliable calculation is:
menu price = cost per portion ÷ target food cost percentage
Write the percentage as a decimal. If a dish costs £2.40 per portion and the target food cost is 28%, the unrounded price is £2.40 ÷ 0.28 = £8.57. The calculation gives you a starting price; the final number still needs to make sense for the portion, service, local market and VAT treatment.
Start with the amount that actually goes into one serving. A £12 pack of chicken is not automatically a £12 recipe cost. Record the pack size, the usable yield after trimming or cooking, and the quantity used in the recipe.
For a simple ingredient, the calculation is:
cost of quantity used = pack price × quantity used ÷ usable pack quantity
Repeat that calculation for every ingredient, then add the results. If a recipe produces ten portions, divide the batch cost by ten. For ingredients with trim, waste or cooking loss, use the usable quantity rather than the label weight. That is where an apparently cheap dish can become expensive on the plate.
You can check the arithmetic with the free food cost calculator or use the recipe costing and batch scaling tool when the dish is a batch recipe.
Once you have a defensible portion cost, divide it by the target percentage as a decimal. For example:
These are worked examples, not recommended targets. The right percentage depends on your operating model and what else the selling price must cover. Keep the target visible so a future price change does not quietly turn a 28% dish into a 35% dish.
Do not round the portion cost before the final division. Keep the unrounded result in your worksheet, then choose a customer-facing price. A price of £8.57 might become £8.50, £8.75 or £9.00 depending on the menu and service style. Recalculate the achieved food cost after rounding so you know what changed.
Decide whether the input prices and selling price are being treated inclusive or exclusive of VAT, and use the same basis throughout. For a restaurant menu, also keep service charges, delivery charges and discounts separate from the food-cost calculation. Mixing them into the ingredient percentage makes comparisons unreliable.
A menu price based on last season’s invoice is only a snapshot. Keep pack price, pack size, yield and date together. When a major ingredient changes, update the affected dishes and compare the new achieved percentage with the target. That makes the change explainable to whoever buys stock, writes the menu or approves a price change.
For a repeatable worksheet rather than a one-off calculation, the PrepSheet costing templates keep the working inputs in one place. Start with the free calculator, then buy a template only if it saves time in your actual workflow.