How to Calculate the Food Cost of a Dish (Step by Step)
The food cost formula, a worked example dish by dish, and the mistakes to avoid. Learn to work out what each plate really costs you to make.
How much does the dish you're about to send out actually cost you? Not the price the customer pays, but the real bill for the ingredients inside it. That's the question food cost answers, and knowing how to calculate it is the difference between a menu that makes you money and one that has you working hard for very little.
The good news: the maths is simple. A formula, a scale, and your invoices. Let's walk through it with an example worked out to the last cent.
What food cost is
Food cost is what the raw ingredients needed to make a dish cost you. It's usually expressed as a percentage of the selling price, so you can compare different dishes against each other and see which ones leave you the most margin.
Don't confuse it with the price of the dish: food cost isn't what you sell it for, it's what the ingredients inside that portion cost. A dish selling at 14 € with 3 € of ingredients has a food cost of 21%.
The formula
The base formula is a single one and never changes:
Food cost % = (ingredient cost ÷ selling price) × 100
The trick is to work out the cost of the actual portion, not the whole pack. If you buy a kilo of cheese and use 25 grams, only the cost of those 25 grams goes into the food cost, not the entire kilo. For that you need just one thing: the price per kilo (or per litre) of each ingredient, which you'll find on your supplier invoices.
A worked example: fish and chips
Let's take a real dish and calculate it all the way through. A plate of fish and chips you sell at 13.50 €. Here are the ingredients in one portion, with weights and costs:
| Ingredient | Quantity | Cost |
|---|---|---|
| Cod fillet | 180 g | 2.70 € |
| Potatoes (chips) | 250 g | 0.35 € |
| Batter (flour, beer) | q.b. | 0.30 € |
| Peas, tartare sauce | q.b. | 0.40 € |
| Oil, salt, lemon | q.b. | 0.25 € |
| Total | 4.00 € |
Now apply the formula, step by step:
- Add up the ingredient costs: 2.70 + 0.35 + 0.30 + 0.40 + 0.25 = 4.00 €
- Divide by the selling price: 4.00 ÷ 13.50 = 0.2963
- Multiply by 100: 0.2963 × 100 = 29.6%
The food cost of this fish and chips is 29.6%. The margin on raw ingredients is therefore 9.50 € per plate (13.50 − 4.00). A clean number that tells you exactly how hard that dish is working for you.
Why it really matters
Plenty of operators glance at the till at the end of the day and think that's enough. But takings tell you nothing about your real margin. You can have a packed service and still make little, if the dishes that sold most had a high food cost.
Food cost shifts your attention to what counts: not "how much did I take", but "how much did I keep" on each dish. It's the only way to price a menu with any rigour, to know which dishes to protect and which to rethink, and to catch it in time when a supplier bumps their prices and quietly eats into your margin.
The most common mistake: guessing by eye
Guessing by eye is the mistake that costs the most. "That dish is probably three or four euros of ingredients" is a sentence I've heard a thousand times, and it's almost always wrong. Here's where the real number slips out of view:
- The invisible ingredients. Oil, salt, spices, garnishes, the drizzle to finish. On their own they're a few cents, but on every plate they add up and move the percentage.
- Costs that change. The cod you were paying 12 €/kg now costs 15. If you don't update the calculation, you still believe you have the margin from six months ago.
- Portions creeping up. Twenty grams extra per plate, times hundreds of covers a month, is real money walking out the door.
Guessing by eye is fine for a five-second gut check. For pricing a menu, it isn't.
How to do it fast from your invoices
Calculating a single dish is easy. The problem starts when you have forty dishes on the menu, each with ten ingredients, and supplier prices change every month. Doing it all by hand, one spreadsheet after another, is the tedious part almost nobody manages to keep up to date.
The fast method starts where the real numbers already live: your supplier invoices. That's where the actual, up-to-date price of each ingredient sits. From there you work out the cost per gram and apply it to the weights in your recipes. Done once, each dish's food cost updates itself every time a new invoice comes in.
Try AFLUYO
Typing in every invoice by hand, working out the cost per gram, and recalculating each dish's food cost whenever prices change is a long, repetitive job. AFLUYO reads your real supplier invoices directly and automatically calculates the food cost and margin of every dish, keeping them up to date as prices move. Try it free for 7 days, no card.