Your cash register tracks revenue, but that's only half the story. You need to connect those sales figures to your actual ingredient costs to see which dishes truly make money. Without this link, you're flying blind on profitability.
Gather the right cash register data
You don't need every number from your register. Focus on these three essentials:
- Number of portions sold per dish - not just the revenue
- Selling price per dish - excluding VAT for the calculation
- Period - weekly or monthly for consistent comparison
💡 Example register data:
Sold last week:
- Steak: 45 portions at €32.00
- Salmon: 38 portions at €28.50
- Pasta: 67 portions at €18.50
These numbers form your foundation for food cost analysis.
Calculate the selling price excluding VAT
Most registers show prices with VAT included. But you need the price without VAT for accurate food cost calculations.
Formula: Selling price excl. VAT = Selling price incl. VAT / 1.09
💡 Example VAT calculation:
- Steak €32.00 incl. VAT → €32.00 / 1.09 = €29.36 excl. VAT
- Salmon €28.50 incl. VAT → €28.50 / 1.09 = €26.15 excl. VAT
- Pasta €18.50 incl. VAT → €18.50 / 1.09 = €16.97 excl. VAT
⚠️ Note:
Always work with VAT-excluded prices. Otherwise your food costs will look artificially low, leading to poor business decisions.
Link register figures to ingredient costs
Now you connect your sales data to your actual recipe costs:
- Ingredient costs per portion - total all ingredients that go on the plate
- Food cost percentage - (ingredient costs / selling price excl. VAT) × 100
- Profit per portion - selling price excl. VAT minus ingredient costs
💡 Example complete calculation:
Steak (45 portions sold):
- Selling price excl. VAT: €29.36
- Ingredient costs: €10.20
- Food cost: (€10.20 / €29.36) × 100 = 34.7%
- Profit per portion: €29.36 - €10.20 = €19.16
- Total profit: 45 × €19.16 = €862.20
Analyze your profitability per dish
From tracking this across dozens of restaurants, you'll quickly spot patterns in which dishes drive real profit:
- Food cost percentage - aim for below 35% in most restaurants
- Total profit per dish - portions sold × profit per portion
- Popularity vs profitability - your bestsellers might not be your money-makers
💡 Example analysis:
Comparison of three dishes:
- Pasta: 67 portions, €6.97 profit/portion = €467 total
- Salmon: 38 portions, €17.15 profit/portion = €652 total
- Steak: 45 portions, €19.16 profit/portion = €862 total
Pasta's your volume leader, but steak drives the most profit.
⚠️ Note:
Keep your ingredient prices current. Suppliers raise prices constantly, but menu prices often lag behind. This kills your calculation accuracy.
Use these insights for better decisions
With register data linked to food costs, you can make data-driven menu decisions:
- Menu engineering - push profitable dishes harder
- Price adjustments - fix dishes with excessive food costs
- Recipe modifications - tweak portions or substitute ingredients
- Purchasing optimization - prioritize ingredients for your profit drivers
Tools like KitchenNmbrs automatically connect recipes to sales data, eliminating manual calculations entirely.
How do you link register figures to food cost? (step by step)
Export sales figures from your register
Get the number of portions sold and selling price for each dish. Choose a fixed period like a week or month so you can see trends.
Convert all prices to excluding VAT
Divide each selling price by 1.09 to convert from including to excluding VAT. This is crucial for an accurate food cost calculation.
Calculate ingredient costs per portion
For each dish, add up all ingredients that go on the plate. Don't forget garnishes, sauces and oil - everything counts toward the cost price.
Calculate food cost and profit per dish
Use the formula: (ingredient costs / selling price excl. VAT) × 100 for food cost percentage. Subtract ingredient costs from selling price for profit per portion.
Analyze and prioritize your actions
Start with your best-selling dishes. If those have a food cost above 35%, you'll capture the biggest profit there. Multiply profit per portion by number of sales for total impact.
✨ Pro tip
Pull your top 3 revenue-generating dishes every 2 weeks and verify their ingredient costs haven't crept up. These dishes often mask profit erosion across your entire menu.
Calculate this yourself?
In the KitchenNmbrs app you can do this in just a few clicks. 7 days free, no credit card.
Was this article helpful?
Frequently asked questions
Do I need to analyze all dishes or can I select some?
Start with your 5-10 bestsellers. These generate roughly 80% of your revenue and profit. Master these first, then expand your analysis.
How often should I do this linking?
Monthly at minimum to catch trends early. But recalculate immediately when supplier prices jump, or your numbers become meaningless.
What if my cash register system doesn't have detailed reports?
Track manually for one week - count every dish sold. It's tedious but gives you solid baseline data for your most popular items and their true profitability.
How do I handle fluctuating ingredient prices?
Update ingredient costs monthly minimum. For volatile items like seafood or produce, check weekly. Price inflation kills profit margins faster than most owners realize.
📚 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.
Calculate it yourself with KitchenNmbrs
All the formulas you learn here — KitchenNmbrs calculates them automatically. Enter your ingredients and instantly see your food cost, margin, and selling price. Try it free for 14 days.
Start free trial →