Most food truck owners think they know their fries cost until they realize they've been losing money for months. You calculate the potato cost, set your price, but forget about oil consumption, packaging, and those "small" extras. These overlooked costs can eat 20-30% into your profits without you noticing.
What's included in the cost price of fries?
A portion of fries consists of more than just potatoes. For a correct cost price calculation, you add up all ingredients and materials:
- Potatoes (fresh or frozen)
- Frying oil or fat (consumption per portion)
- Salt (small amount, but it adds up)
- Packaging (box, bag, or paper cone)
- Napkins (often forgotten)
- Gas/electricity for the fryer (optional, for accuracy)
⚠️ Watch out:
Many food truck owners only calculate with potato costs. The oil and packaging together can be an extra 20-30% in costs.
Calculate the potato costs per portion
Start with your main ingredient. Fresh potatoes need waste factored in, frozen fries don't.
💡 Example fresh potatoes:
You buy 10 kg of potatoes for €8.50. After peeling and cutting you have 7.5 kg of fries left.
- Purchase price: €8.50 per 10 kg = €0.85 per kg
- Cutting waste: 25% (peel, eyes, bad pieces)
- Actual price: €0.85 / 0.75 = €1.13 per kg usable fries
- Portion of 200 grams: €1.13 × 0.2 = €0.23
💡 Example frozen fries:
You buy 10 kg of frozen fries for €18.00. No cutting waste, but some shrinkage occurs during frying.
- Purchase price: €18.00 per 10 kg = €1.80 per kg
- Portion of 200 grams: €1.80 × 0.2 = €0.36
- Shrinkage of 5%: €0.36 / 0.95 = €0.38
Calculate the oil consumption per portion
Frying oil gets used and replaced regularly. You need to figure out exactly how much oil gets "consumed" per portion served. This is one of the most common blind spots in kitchen management - operators either ignore it completely or wildly overestimate the replacement frequency.
Oil consumption formula:
Oil costs per portion = (Price per liter of oil / Number of portions per fill) + Absorption per portion
💡 Example oil calculation:
Your fryer holds 20 liters of oil at €2.50 per liter. You replace the oil after 500 portions of fries.
- Total oil costs: 20L × €2.50 = €50.00
- Costs per portion (replacement): €50.00 / 500 = €0.10
- Absorption per portion: approximately €0.02
- Total oil costs per portion: €0.12
Add salt and packaging
These costs seem tiny, but they multiply fast at high volumes. Calculate realistically based on what you actually use per portion.
- Salt: approximately 2 grams per portion = €0.01
- Fries box: €0.08 - €0.15 per piece
- Napkins: 2 pieces = €0.02
- Mayonnaise packet (optional): €0.12 - €0.18
💡 Complete cost price calculation:
Portion of fries (200 grams) with box and napkins:
- Frozen fries: €0.38
- Frying oil: €0.12
- Salt: €0.01
- Fries box: €0.10
- Napkins: €0.02
Total cost price: €0.63 per portion
Determine your selling price and margin
With your true cost price, you can calculate food cost percentage and selling price. Food trucks typically target 25-35% food cost.
⚠️ Watch out:
Always calculate excluding VAT. A portion of fries at €3.00 incl. 9% VAT is €2.75 excl. VAT for your food cost calculation.
Formula minimum selling price:
Selling price excl. VAT = Cost price / (Desired food cost % / 100)
💡 Price calculation example:
Cost price €0.63, desired food cost 30%:
- Minimum price excl. VAT: €0.63 / 0.30 = €2.10
- Price incl. 9% VAT: €2.10 × 1.09 = €2.29
- Rounded: €2.50 on the menu
- Actual food cost: €0.63 / (€2.50 / 1.09) = 27.5%
Account for variable costs
Ingredient prices fluctuate constantly. Check your cost price regularly and adjust pricing accordingly.
- Potato prices vary by season (€0.40 - €1.20 per kg)
- Frying oil rises with global oil prices
- Packaging becomes more expensive due to environmental regulations
- Energy costs affect your total margin
How do you calculate the cost price of fries? (step by step)
Calculate the potato costs per portion
Divide the purchase price by the number of portions you get from it. For fresh potatoes, account for 20-25% cutting waste. For frozen fries, add 5% shrinkage during frying.
Calculate the oil consumption
Divide the costs of a full oil fill by the number of portions you fry with it. Add the oil absorption per portion to that (approximately €0.02 per 200 gram portion).
Add all extra costs
Calculate salt (€0.01), packaging (€0.08-€0.15), and napkins (€0.02) per portion. These small amounts can together make up 15-20% of your cost price.
Determine your selling price
Divide your total cost price by your desired food cost percentage (for example 30%). Multiply by 1.09 for VAT and round to a practical menu price.
✨ Pro tip
Weigh your actual fry portions for 3 consecutive service days, not just once. Most operators unconsciously vary portion sizes during busy periods, and that 180g portion can easily become 240g during rush times - inflating your real cost by 33%.
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 include frying oil costs in my calculation?
Absolutely. Frying oil represents real money leaving your pocket with every batch. Calculate approximately €0.10-€0.15 per portion for oil consumption and replacement. Many operators skip this and wonder why their margins are lower than expected.
What food cost percentage is normal for fries in a food truck?
Food trucks typically target 25-35% overall food cost. Fries often run lower at 20-30% because they're inexpensive to make, which helps offset pricier ingredients in other menu items.
How often should I recalculate my fries cost price?
Check every 8-10 weeks minimum, or immediately after major price changes from suppliers. Potato and oil prices can swing 15-25% seasonally. If your cost price jumps more than 10%, you need to adjust menu prices or portion sizes.
📚 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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