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How do I cost a recipe? A step-by-step guide for professional kitchens

By the Prepsheets team · Published 20 July 2026 · 6 min read

To cost a recipe, list every ingredient with its purchase price and pack size, work out the cost of the quantity actually used (adjusted for yield), add a wastage allowance, sum the ingredient costs for a batch cost, then divide by the number of portions. Compare the per-portion cost to your ex-VAT selling price to get your gross profit margin. Here's the full process.

Step 1: List every ingredient — including the small stuff

Oil, seasoning, garnishes and sauces are where recipe costings quietly go wrong. A "2% sundries allowance" is acceptable, but costing them properly is better. If a dish has a marinade or a sub-recipe (a stock, a dressing), cost that recipe first and use its per-unit cost as an ingredient.

Step 2: Convert pack price to unit cost

Divide the purchase price by the pack size to get a cost per gram, ml or unit. A 5kg case of chicken thighs at €38.50 is €0.0077/g — so a 180g portion costs €1.39.

Step 3: Adjust for yield

Raw weights lie. Trimming, peeling and cooking loss mean the usable amount is less than what you bought. If chicken thighs lose 15% in trimming and cooking, the real cost of a 180g served portion is €1.39 ÷ 0.85 = €1.63.

The most common mistake: skipping yield is the single most common reason kitchens think they're at 70% GP when they're at 63%.

Step 4: Add a wastage allowance

Even well-run kitchens waste 5–10% of fresh produce and proteins through spoilage, over-prep and plate waste. Build it into the costing rather than discovering it in the monthly stocktake.

Step 5: Total, divide, compare

Sum the adjusted ingredient costs for the batch, divide by portions, and compare with your selling price excluding VAT:

GP% = (ex-VAT price − portion cost) ÷ ex-VAT price × 100

Most restaurants target 65–70% GP on food (see: What is a good gross profit margin for a restaurant?).

Step 6: Keep it up to date — this is the hard part

A recipe costing is a snapshot. Supplier prices change weekly, and a costing done in January can be badly wrong by summer. Options:

Written by the Prepsheets team — built by chefs with 25+ years running professional kitchens.

Know your target margin

Once your recipes are costed, benchmark them: what GP should your type of operation actually be hitting?

What is a good GP margin? →