Most restaurants lose 5-15% extra profit by ignoring waste in their food cost calculations. Factor cutting loss, spoilage, and portion variance into your costs using the adjusted formula: (Purchase costs / Yield %) / Selling price × 100.
How much money are you throwing in the bin each week without even realizing it? Most restaurant owners track their food purchases religiously but completely ignore waste - turning what looks like a 28% food cost into an actual 35% disaster. Here's how to factor waste into your cost calculations so you know your real numbers.
What counts as waste in your food cost?
Waste is everything you buy but can't sell. This goes way beyond spoiled lettuce.
- Cutting loss: Bones, fish bones, peels, fat
- Portion loss: Oversized portions, spillage, tasting
- Spoilage: Products past their date, stored incorrectly
- Failed dishes: Burnt, incorrectly prepared
- Customer returns: Dishes sent back
💡 Example: Salmon cutting loss
You buy 2 kg whole salmon for €18/kg = €36 total
- Head, bones, skin: 0.9 kg (45% loss)
- Usable fillet: 1.1 kg
Actual fillet price: €36 / 1.1 kg = €32.73/kg
The correct formula for food cost including waste
The standard food cost formula doesn't account for waste. You need to adjust it:
Adjusted food cost = (Purchase costs / Yield %) / Selling price excl. VAT × 100
Where: Yield % = 100% - Waste %
💡 Example: Steak with cutting loss
Steak on menu: €32.00 (incl. 9% VAT) = €29.36 excl. VAT
- Purchase whole piece of meat: €8.00
- Cutting loss (fat, sinews): 20%
- Yield: 80%
Actual cost price: €8.00 / 0.80 = €10.00
Food cost: (€10.00 / €29.36) × 100 = 34.1%
⚠️ Note:
Without waste, your food cost would be 27.2%. With waste, it's actually 34.1%. A difference of almost 7 percentage points!
Calculating different types of waste
Cutting loss (most common)
With fresh products that you process yourself:
- Weigh the product before and after processing
- Calculate the loss percentage
- Divide your purchase price by the yield
💡 Example: Onion cutting loss
- 5 kg onions purchased for €1.20/kg
- After peeling: 4.5 kg usable
- Loss: 0.5 kg = 10%
- Yield: 90%
Actual price: €1.20 / 0.90 = €1.33/kg
Portion loss
Chef gives more than the standard portion:
- Measure actual portions for a week
- Compare with your standard portion
- Calculate the cost difference
Spoilage and returns
Harder to predict, but worth including:
- Track what you throw away for 2 months
- Calculate the average loss percentage
- Add this to your other losses
Waste per product category (guidelines)
From analyzing actual purchasing data across different restaurant types, here are typical loss percentages:
- Fish (whole to fillet): 40-55%
- Meat (whole to portions): 15-25%
- Vegetables (peeling): 10-25%
- Lettuce and leafy greens: 15-30%
- Fruit: 20-40%
- Herbs (wilting): 20-35%
⚠️ Note:
These are guidelines. Measure yourself for a couple of weeks to know your own loss percentages. Every kitchen is different.
Impact of waste on an annual basis
Small loss percentages have massive consequences:
💡 Example: Impact of 5% extra waste
Restaurant with €400,000 annual turnover and 30% food cost:
- Annual ingredient costs: €120,000
- 5% extra waste: €6,000 per year
- Per month: €500 extra costs
This is pure profit loss that you can prevent
Tracking waste in practice
Three ways to monitor waste:
- Manual: Weigh and note everything you throw away
- Excel: Create a list per product category
- Digital: Use specialized software to track waste per ingredient
The most important thing is that you track it at all. Many kitchens throw away tens of euros daily without realizing it.
How do you calculate food cost including waste? (step by step)
Measure your actual waste
Track for 2 weeks how much you throw away per product category. Weigh the waste and note the purchase value. Calculate the loss percentage per product.
Calculate your yield percentage
Yield = 100% minus waste%. With 20% waste, your yield is 80%. You need this percentage for the cost price calculation.
Adjust your cost price formula
Divide your purchase costs by the yield percentage. With €8 purchase and 80% yield: €8 / 0.80 = €10 actual cost price per portion.
Calculate your new food cost percentage
Divide the adjusted cost price by your selling price excl. VAT and multiply by 100. Remember: always use the price excluding VAT.
Monitor and adjust where needed
Check monthly whether your loss percentages are correct. Adjust your menu prices if your food cost becomes too high due to waste.
✨ Pro tip
Track waste on your three most expensive ingredients for 10 days straight. These high-cost items typically account for 60% of your total waste expense, so fixing them first gives you the biggest return.
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In the KitchenNmbrs app you can do this in just a few clicks. 7 days free, no credit card.
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Frequently asked questions
Should I include all waste in my food cost?
Yes, everything you buy but can't sell increases your actual cost price. Even small loss percentages have a big impact on an annual basis.
How often should I update my loss percentages?
Check this monthly. Loss percentages can change due to season, supplier, or new kitchen staff.
What if my food cost becomes too high due to waste?
You have three options: reduce waste through better planning, adjust portions, or increase your selling price to restore your margin.
Can I use loss percentages from the internet?
Use them as a starting point, but measure yourself. Every kitchen has different loss percentages due to working methods, supplier, and type of products.
📚 Sources consulted
- EU Verordening 852/2004 — Levensmiddelenhygiëne (2004) — Official source
- EU Verordening 853/2004 — Hygiënevoorschriften voor levensmiddelen van dierlijke oorsprong (2004) — Official source
- EU Verordening 1169/2011 — Voedselinformatie aan consumenten (2011) — Official source
- NVWA — Hygiënecode voor de horeca (2024) — Official source
- NVWA — Allergenen in voedsel (2024) — Official source
- Codex Alimentarius — International Food Standards (2024) — Official source
- FSA — Safer food, better business (HACCP) (2024) — Official source
- BVL — Lebensmittelhygiene (HACCP) (2024) — Official source
- Warenwetbesluit Bereiding en behandeling van levensmiddelen (2024) — Official source
- WHO — Foodborne diseases estimates (2024) — Official source
Food Standards Agency (FSA) — https://www.food.gov.uk
The HACCP standards shown in this application are for informational purposes only. KitchenNmbrs does not guarantee that displayed values are current or complete. Always consult the FSA or your local authority for the latest regulations.
Written by
Jeffrey Smit
Founder & CEO of KitchenNmbrs
Jeffrey Smit built KitchenNmbrs from 8 years of hands-on experience as kitchen manager at 1NUL8 Group in Rotterdam. His mission: give every restaurant owner control over food cost.
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