Most restaurant owners think they know their ingredient costs - but they're often off by 15-30%. The culprit? Miscalculating cost price per gram or liter. You can't price dishes accurately if you don't know what each gram actually costs you.
Why cost price per gram matters
You buy meat per kilo, but sell per portion. You buy vegetables per kilo, but use 150 grams per plate. To calculate your food cost correctly, you need to know what one gram or one milliliter really costs.
💡 Example:
You buy beef for €24.00 per kilo. Per portion you use 200 grams.
- Cost price per gram: €24.00 ÷ 1000 = €0.024
- Cost per portion: 200 × €0.024 = €4.80
Beef costs €4.80 per portion
The basic formula
The same formula applies to all ingredients:
Cost price per unit = Total purchase price ÷ Number of units
- For solid products: price per kilo ÷ 1000 = price per gram
- For liquids: price per liter ÷ 1000 = price per milliliter
- For pieces: price per package ÷ number of pieces = price per piece
Including trim loss
With fresh products you always have waste. Peels, bones, fat you throw away. This makes your ingredients more expensive than the purchase price suggests. Missing this detail is a mistake that costs the average restaurant EUR 200-400 per month in underpriced dishes.
💡 Example trim loss:
Whole salmon: €18.00 per kilo. After filleting you have 55% usable meat.
- Yield: 55% = 0.55
- Real fillet price: €18.00 ÷ 0.55 = €32.73 per kilo
- Per gram: €32.73 ÷ 1000 = €0.033 per gram
Salmon fillet costs €0.033 per gram
⚠️ Note:
With trim loss you divide by the yield, you don't multiply! 45% loss means 55% yield. The fillet becomes more expensive, not cheaper.
Converting different units
Suppliers use different units. You need to convert everything to what you actually use.
- Kilograms to grams: × 1000
- Liters to milliliters: × 1000
- Packages to pieces: ÷ number per package
💡 Example different units:
Olive oil: €12.50 per liter. You use 15 ml per dish.
- Per milliliter: €12.50 ÷ 1000 = €0.0125
- Per 15 ml: 15 × €0.0125 = €0.19
Olive oil costs €0.19 per dish
Practical examples by category
Meat and fish:
- Whole chicken €3.50/kg → after boning 65% yield → €5.38/kg usable meat
- Beef tenderloin €28/kg → no loss → €0.028 per gram
- Unpeeled shrimp €22/kg → 60% yield → €36.67/kg peeled shrimp
Vegetables:
- Potatoes €1.20/kg → 15% peeling loss → €1.41/kg peeled
- Onions €0.80/kg → 10% loss → €0.89/kg clean
- Lettuce €2.50/head → 80% usable → €3.13 per head clean
Tracking cost price in practice
Manual calculations take tons of time. Especially when suppliers change prices. Many hospitality entrepreneurs use systems to automatically track cost prices per gram.
⚠️ Note:
Update your cost prices regularly. Suppliers raise prices without you noticing. Check your main ingredients at least monthly.
How do you calculate cost price per gram? (step by step)
Gather purchase prices and package sizes
Write down the exact purchase price and how much you get. Pay attention to units: some suppliers charge per kilo, others per piece or per package.
Calculate the actual yield
Weigh the product before and after processing. Subtract peels, bones and waste. The yield is what you actually use divided by what you purchase.
Calculate the real cost price
Divide the purchase price by the yield, then by the number of grams. Formula: (purchase price ÷ yield) ÷ 1000 = cost price per gram.
✨ Pro tip
Test your yield calculations on 3 different deliveries before setting your percentages. Salmon from different suppliers can vary from 52% to 58% yield - that's a €3 difference per kilo.
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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 VAT in my cost price per gram?
No, the purchase price of ingredients is always excluding VAT. You do pay VAT to your supplier, but you can claim it back from the Tax Authority.
How often should I update my cost prices per gram?
At least monthly for your main ingredients. Suppliers regularly raise prices. Check especially meat, fish and dairy, as these fluctuate the most.
Should I also calculate herbs and spices per gram?
Yes, even if you use small amounts. Saffron costs €30 per gram for example. Even a pinch can affect your food cost.
How do I handle seasonal products that vary greatly in price?
Calculate a yearly average or adjust your menu per season. Tomatoes cost 3× more in winter than in summer. Plan your menu accordingly.
📚 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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