Catering Yield and Food Waste Calculator
This catering yield calculator applies trim loss and cooking loss in sequence to give the combined edible yield, the raw quantity to buy for a target, and the total need for your guests. As purchased (AP) and edible portion (EP) weights are kept separate throughout.
Calculated results
Preparation and cooking losses apply successively to different bases: they cannot simply be added together.
Method and limits
How to use this calculator
Enter the raw, as purchased quantity, the yield after preparation — trimming, peeling, boning — and the additional cooking loss: the result shows the final quantity and the combined yield. To size an event, enter your target net quantity: the required raw quantity appears, along with the need computed from the number of guests and the portion per person.
The quantity after preparation is Q_1 = Q_raw × Y_1/100, then the final quantity is Q_final = Q_1 × (1 − L_2/100); the combined yield is Y_total = (Y_1/100) × (1 − L_2/100) × 100. The raw quantity required for a target comes from division: Q_required = Q_target / ((Y_1/100) × (1 − L_2/100)). The losses do not add up — they multiply.
Sequential losses and combined yield
Trim loss applies to the as purchased (AP) weight; cooking loss applies to the already-trimmed weight. Adding 15% and 15% into a single 30% overstates the total loss: the correct sequence gives 85% × 85% = 72.25% combined yield. A zero preparation yield and a 100% cooking loss are blocking errors, since the required raw quantity becomes undefined.
Sizing for your guests
The guests' net need is Q_guests = N × P / 1000, with N the number of guests and P the portion in grams. Compare that value with your target quantity to validate the sizing, then let the calculator work back to the raw purchase. A portion above 1 kg (2.2 lb) per guest triggers a warning without blocking: some festive dishes justify it. Leftovers are neither subtracted nor added automatically.
Worked example
With 10 kg (about 22 lb) raw, an 85% trim yield and a 15% cooking loss: 8.5 kg trimmed, then 7.225 kg finished — a 72.25% combined yield. To serve a 10 kg net target, the raw purchase must reach 13.841 kg (30.5 lb); 50 guests at 150 g (5.3 oz) each need 7.5 kg net. Reproduce these values in the tool: you must get exactly the same results.
Assumptions and limits
Preparation and cooking losses apply successively to different bases: they cannot simply be added together. The yields you enter depend on the product, the trimming practiced and the cooking method — food-service reference tables remain indicative averages. Leftovers, second servings and extra guests are not provided for: build them voluntarily into the target or the portion. The calculation assumes losses are uniform across the whole quantity processed.
Frequently asked questions
Limits of use