Food cost for a New Zealand menu, dish by dish
Food cost is the cost of the ingredients in a portion, divided by the selling price excluding GST. It is worked out from a recipe card, not from memory. This guide shows the formula, a complete recipe card with illustrative figures and the common places where food cost goes wrong.
The formula, in short
- List every ingredient with its net weight, exactly as it lands on the plate.
- Divide the purchase price by the unit of measure and multiply it by the weight on the recipe card.
- Add technical loss: what goes in cleaning, trimming and cooking.
- Add up all the lines. The total is the production cost of one portion.
- Divide the production cost by the menu price excluding GST: food cost % = cost ÷ price excl. GST × 100.
A complete recipe card: carbonara, one portion
Recipe card with weights, purchase prices and plated cost (illustrative figures)
| Ingredient | Net weight | Purchase price | Plated cost |
|---|---|---|---|
| Spaghetti | 120 g | $9.00/kg | $1.08 |
| Guanciale | 60 g | $45.00/kg | $2.70 |
| Egg yolks (2) | 40 g | $0.55 each | $1.10 |
| Pecorino | 30 g | $90.00/kg | $2.70 |
| Pepper, salt, oil | — | — | $0.25 |
| Total raw materials | 250 g | — | $7.83 |
| Final cost (incl. 5% technical loss) | — | — | $8.22 |
What the example tells you
The menu price is $36.00 including GST. At 15% GST, the price excluding GST is 36.00 ÷ 1.15 = $31.30.
Food cost = 8.22 ÷ 31.30 = 26.3%, so $8.22 of every $31.30 excluding GST goes on ingredients.
A result like that is only as good as the recipe behind it. If food cost climbs past your own target, you have three options: raise the price, reduce the portion or change supplier for the priciest ingredient. Here, the pecorino and guanciale make up about two-thirds of the cost.
Yield matters more than the price on the invoice
Example: you buy beef tenderloin at $120/kg. After trimming, 780 g per kilo is usable, a 78% yield.
The real cost of the meat that reaches the plate is not $120/kg but 120 ÷ 0.78 = $153.85/kg. A recipe card that ignores yield understates the meat cost by almost 22%.
Rule of thumb: for meat, fish and root vegetables, record the yield you measure in your own kitchen, not the figure from a textbook.
What the rules say
- The recipe card is your internal record of what goes into each dish, and the starting point for your allergen information.
- Allergen information for food you serve should follow the labelling rules in the Australia New Zealand Food Standards Code. Check the detail with your food safety adviser.
- Menu prices and portion sizes must be clear and not misleading. The Fair Trading Act 1986 applies to what you tell customers.
- GST is 15%, and restaurant meals carry the standard rate, so food cost is always measured against the price excluding GST.
- If a recipe change alters the allergens, update the menu that guests see straight away.
Common mistakes
- Dividing by the GST-inclusive price, which makes the result about 13% lower than reality.
- Using the gross weight from the supplier invoice instead of the net weight on the plate.
- Forgetting the side, the sauce and the packaging. Small lines like these add up across a menu.
- Updating the recipe card once a year, even though purchase prices change often.
- Looking only at the percentage and ignoring how many dollars remain from each portion sold, which is what counts at month end.
How 4restaurants.net helps
- Each dish has a recipe card with weights, and the production cost is calculated from it.
- Net weights on the recipe card let trimming enter the calculation correctly.
- The QR digital menu links to the same recipe cards, in the same application.
- Food cost sits next to each dish, in the same application as the reports by dish.