Nearly 78% of restaurants lose money on food costs they never see coming. Gross purchases show what you order and pay suppliers, while net consumption reveals what actually reaches your guests' plates. The gap between these numbers exposes where your profits disappear daily.
What is gross purchases?
Gross purchases represents the total value of all products you buy. It's the amount on your invoices and what you pay suppliers.
- Whole salmon of 2 kg for €36
- 10 kg potatoes for €8
- 5 liters cream for €15
Your gross purchases calculation is straightforward: add up all purchase invoices.
? Example:
Restaurant De Smulhoek purchases this week:
- Meat and fish: €1.200
- Vegetables: €400
- Dairy: €300
- Other: €200
Gross purchases: €2.100
What is net consumption?
Net consumption shows the actual value of ingredients that reach your guests' plates. This figure stays consistently lower than gross purchases due to:
- Cutting loss: bones, skin, fat, trimmings
- Waste: spoiled products, discarded mise-en-place
- Staff consumption: employee meals
- Tasting and testing: chef samples during cooking
? Example:
From that €2.100 gross purchases, the following gets lost:
- Cutting loss fish: €180 (15%)
- Vegetable waste: €40 (10%)
- Staff meals: €150
- Other loss: €80
Net consumption: €2.100 - €450 = €1.650
Why this difference matters
The gap between gross purchases and net consumption reveals hidden costs - expenses you incur but don't directly see in your dishes.
⚠️ Watch out:
Many operators only calculate with gross purchases for their food cost. Then your food cost appears lower than reality. You're losing money without realizing it.
In the example above:
- Gross purchases: €2.100
- Net consumption: €1.650
- Difference: €450 (21% loss!)
This €450 isn't reaching your dishes, but you're paying for it anyway. That's €1.800 monthly in extra costs you don't recover.
How do you calculate the difference?
The formula stays simple:
Loss percentage = ((Gross purchases - Net consumption) / Gross purchases) × 100
? Example calculation:
Gross purchases: €2.100
Net consumption: €1.650
Loss: ((€2.100 - €1.650) / €2.100) × 100 = 21.4%
For every €100 you purchase, €78.60 reaches the plates.
Typical loss percentages
Every restaurant experiences loss, but amounts vary significantly:
- Well-managed kitchen: 15-20% loss
- Average kitchen: 20-25% loss
- Poorly managed kitchen: 25-35% loss
Above 25% loss drains serious money. Every 5% improvement saves hundreds of euros monthly.
Where does it go wrong?
The biggest loss items often include:
- Underestimated cutting loss: whole fish has 40-50% loss, not 20%
- No FIFO: old products get discarded, new ones remain
- Over-portioning: chef serves more than calculated
- Poor storage: products spoil faster
⚠️ Watch out:
If you don't know your net consumption, you can't calculate accurate food cost. Your food cost will appear lower than reality.
How do you get control of the difference?
Step 1 involves measuring. You can't improve what you don't track:
- Count your inventory weekly (beginning and end of week)
- Track what you discard and why
- Measure cutting loss on large products (fish, meat)
- Register staff meals
From years of working in professional kitchens, I've seen how tracking systems like KitchenNmbrs help you monitor this digitally. You immediately see the difference between what you purchase and what actually gets consumed.
Related articles
How do you calculate the difference between gross purchases and net consumption?
Add up your total gross purchases
Get all your purchase invoices from a week and add them up. This is your gross purchases - the amount you actually paid to suppliers.
Calculate your net consumption
Subtract all loss items from your gross purchases: cutting loss, waste, staff meals and other loss. This gives you net consumption.
Calculate the loss percentage
Use the formula: ((Gross purchases - Net consumption) / Gross purchases) × 100. This percentage shows how much of your purchases doesn't end up on the plates.
✨ Pro tip
Track your loss by category for exactly 14 days: separate cutting waste, spoilage, over-portioning, and staff meals. This reveals which area costs you most - often it's over-portioning at 8-12% rather than spoilage.
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
What's the difference between cutting loss and waste in these calculations?
Should I calculate loss percentages differently for proteins versus produce?
How do I account for recipe testing and menu development in net consumption?
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
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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