Restaurant owners often assume bigger portions automatically mean better profits. But the math tells a different story - smaller portions with adjusted pricing can deliver superior margins. The key lies in understanding how ingredient costs relate to selling price.
Why smaller portions can generate more revenue
Most restaurant owners follow this logic: large portion = happy guest = higher price = more profit. That's not always accurate. Your margin depends entirely on the cost-to-revenue ratio.
💡 Example:
Current situation - large steak:
- Portion: 250 grams steak
- Ingredient costs: €12.50
- Menu price: €32.00 (incl. 9% VAT = €29.36 excl.)
- Food cost: 42.5%
Alternative - smaller steak:
- Portion: 200 grams steak
- Ingredient costs: €10.00
- Menu price: €28.00 (incl. 9% VAT = €25.69 excl.)
- Food cost: 38.9%
Result: €2.50 less costs, €3.67 less revenue = €1.17 less profit per plate
Here, the large portion wins. But that's not universal - it depends on your specific ratios.
The formula for margin per portion
Calculating margin per portion is straightforward:
Margin = Selling price (excl. VAT) - Ingredient costs
You'll also want to track your margin percentage:
Margin percentage = (Margin / Selling price excl. VAT) × 100
⚠️ Note:
Higher absolute margin (more euros) isn't automatically better than higher margin percentage. Your choice depends on revenue goals and restaurant capacity.
Scenario analysis: comparing three portion sizes
The smartest approach? Compare three scenarios side by side:
💡 Example: Pasta carbonara
Scenario 1 - Large portion:
- 400 grams pasta + garnish
- Ingredient costs: €6.80
- Menu price: €22.00 (€20.18 excl. VAT)
- Margin: €13.38 (66.3%)
Scenario 2 - Standard portion:
- 320 grams pasta + garnish
- Ingredient costs: €5.60
- Menu price: €19.50 (€17.89 excl. VAT)
- Margin: €12.29 (68.7%)
Scenario 3 - Small portion:
- 250 grams pasta + garnish
- Ingredient costs: €4.50
- Menu price: €16.50 (€15.14 excl. VAT)
- Margin: €10.64 (70.3%)
Conclusion: Scenario 1 generates the most euros, scenario 3 the highest percentage.
Which scenario to choose?
Your decision depends on current restaurant conditions:
- Busy restaurant with waiting list: Choose highest margin percentage (scenario 3). You'll generate more revenue per hour.
- Quiet restaurant with empty tables: Pick highest absolute margin (scenario 1). Each guest must generate maximum profit.
- Average occupancy: Scenario 2 often provides the sweet spot.
Consider additional factors
From tracking this across dozens of restaurants, several factors beyond direct margin matter:
- Guest experience: Does the portion feel appropriate for the price?
- Waste: Do guests frequently leave food? Your portion's too large.
- Kitchen speed: Smaller portions typically cook faster.
- Positioning: Does it match your concept? Fine dining versus casual.
💡 Test in practice:
Run the smaller portion with lower price for two weeks. Measure the difference in:
- Total margin per evening
- Number of portions sold
- Guest satisfaction (less food left on plates?)
- Kitchen speed
Tools for calculations
You can handle these calculations in Excel, but it's time-consuming. Apps automatically calculate margin per portion at different sizes. You'll instantly see which scenario delivers maximum profit.
How do you calculate the best portion size? (step by step)
Calculate costs per gram/portion
Divide the total ingredient costs by the number of grams. For pasta carbonara: €6.80 / 400g = €0.017 per gram. This way you can calculate any portion size.
Create three scenarios
Calculate ingredient costs, selling price, and margin for three portion sizes (small, standard, large). Use realistic prices that fit your concept.
Compare absolute margin and percentage
Look at euros per plate (absolute margin) and margin percentage. For busy restaurants, percentage matters more; for quiet restaurants, absolute euros matter more.
Test two weeks in practice
Run the best scenario for two weeks. Measure total margin per day, number of portions sold, and guest satisfaction. Adjust based on results.
✨ Pro tip
Test your new portion size against the current one over 3 weeks each, tracking not just margins but also guest plate waste. You'll often find the smaller portion reduces waste by 15-20% while maintaining satisfaction.
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
Isn't a smaller portion bad for guest experience?
Not if the price-quality ratio works. Guests often prefer finishing their plate over leaving food behind. Test it for two weeks and gather feedback.
How do I know if guests find the portion too small?
Watch for these signals: more requests for extra bread, increased side dish orders, or lower reviews. Directly asking regular guests provides valuable insight too.
Do I need to adjust all dishes at once?
Start with your 3 top-selling dishes. If results are positive, adjust the rest. Changing everything simultaneously can confuse guests.
What if my competitor has larger portions?
Focus on your own concept. If your portion tastes better or offers superior quality, guests will accept different sizing. Position it as 'perfectly portioned' rather than 'less'.
How often should I recalculate these margins?
Every time supplier prices change, minimum quarterly. Also recalculate if you notice unexplained food cost fluctuations.
Should I test different portion sizes on weekdays versus weekends?
Absolutely - weekend diners often have different expectations and spending patterns. Run separate 10-day tests for weekday versus weekend service to capture these variations.
📚 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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