Waste and trim loss can significantly increase your food cost without you realizing it. Many entrepreneurs only calculate with the purchase price, but forget that you often end up with less usable product.
It's Monday morning and you're staring at last month's P&L wondering where your profits went. You calculated everything perfectly, yet your food costs are 8% higher than expected. The culprit? Waste percentages you never factored into your cost calculations.
Why include waste percentage in your food cost?
If you buy a whole salmon for €18 per kilo, you're not paying €18 per kilo of fillet. With the head, bones, and skin, you only end up with 55% usable meat. Your actual fillet price becomes €32.73 per kilo.
⚠️ Note:
Many entrepreneurs calculate with the purchase price and forget the waste percentage. This makes your food cost appear lower than it actually is.
Types of waste and loss
There are different forms of loss that affect your food cost:
- Trim loss: Bones, fish bones, peels, pits
- Cooking loss: Meat shrinks during frying/grilling
- Spoilage: Products that go past their expiration date
- Portion loss: Oversized portions from the chef
The formula for food cost with waste
The basic formula stays the same, but you first calculate your actual purchase price:
Step 1: Actual purchase price = Purchase price / (Yield % / 100)
Step 2: Food cost % = (Actual costs / Selling price excl. VAT) × 100
💡 Example: Salmon with trim loss
You buy whole salmon for €18.00/kg. After filleting you get 1.1 kg of fillet from a 2 kg salmon.
- Trim loss: 45%
- Yield: 55%
- Actual fillet price: €18.00 / 0.55 = €32.73/kg
For 200g of fillet you pay €6.55 instead of €3.60
Standard waste percentages per product
Use these figures as a guideline for your calculations:
- Fish (whole to fillet): 40-55% loss
- Beef (whole to portions): 15-25% loss
- Shrimp (unpeeled): 35-50% loss
- Vegetables (peels): 15-25% loss
- Fruit (peels, pits): 20-40% loss
💡 Example: Steak with cooking loss
You buy entrecote for €24.00/kg. Due to cooking loss, a 250g steak becomes 200g after grilling.
- Cooking loss: 20%
- You need 250g to get 200g on the plate
- Cost per portion: 0.25 kg × €24.00 = €6.00
Without cooking loss you would calculate €4.80 - a difference of €1.20 per portion
Complete calculation with all losses
For a complete cost price, add up all losses. And here's something you only learn after closing your first month at a loss: every ingredient has hidden waste you don't see until you start weighing everything.
💡 Example: Salmon dish complete
Menu price: €28.00 incl. 9% VAT = €25.69 excl. VAT
- Salmon 180g: €32.73/kg → €5.89
- Vegetables with 20% peel loss: €1.50
- Sauce and garnish: €1.20
- Total ingredient costs: €8.59
Food cost: (€8.59 / €25.69) × 100 = 33.4%
Impact on an annual basis
The difference between accounting for waste and not can be enormous:
⚠️ Note:
If you calculate 5% too low on an annual turnover of €400,000, you miss €20,000 in costs. That could be the difference between profit and loss.
Practical tips for less waste
- Measure your trim loss: Weigh before and after processing for a week
- Train your chef: Consistent portions save money
- Use peels: Make stock or garnish from them
- Rotate inventory: FIFO (First In, First Out) prevents spoilage
How do you calculate food cost including waste? (step by step)
Measure your waste percentage per product
Weigh your products before and after processing for a week. Note the difference between purchase weight and usable weight. Calculate the average waste percentage.
Calculate your actual purchase price
Divide your purchase price by the yield percentage (100% minus waste%). With 30% waste your yield is 70%, so divide by 0.70. This gives you the actual price per usable kilo.
Calculate food cost with actual prices
Use the actual purchase prices to calculate your ingredient costs per portion. Divide this by your selling price excluding VAT and multiply by 100 for the percentage.
✨ Pro tip
Weigh your fish bones and vegetable trimmings for exactly 7 days to get your real waste percentages. Most restaurants discover they're losing 3-5% more than they thought.
Calculate this yourself?
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 also include cooking loss in my calculation?
Yes, cooking loss increases your actual costs. A 250g steak becomes 200g after grilling. So you pay for 250g but serve 200g.
How do I know what a normal waste percentage is?
Measure it yourself for a week. Fish usually has 40-55% loss, meat 15-25%, vegetables 15-25%. This varies per supplier and season.
Can I just estimate waste instead of measuring it?
Estimating is often too optimistic. A difference of 5% on your total purchases can cost thousands of euros per year. Measure it once properly, then you know.
How do I prevent my chef from giving oversized portions?
Use a kitchen scale and agree on portion weights. A difference of 20g meat per portion can cost €3,000+ per year in busy establishments.
📚 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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