Food & Cooking📅 2 April 2025⏱ 4 min read
How to Calculate Food Cost Per Serving for a Restaurant
Food cost percentage is the most critical metric in food service. Here is how to cost each dish, set profitable prices, and track variance.
JW
James WhitfieldPersonal Finance & Maths WriterJames has written about personal finance, health metrics, and everyday mathematics for over six years. He holds a BSc in Mathematics from the University of Leeds.
Restaurants that thrive manage food cost percentage obsessively. Those that fail often discover — too late — that they were selling dishes below cost once all ingredients are properly accounted for.
Cost Per Serving Calculation
Cost per serving = Sum of (Qty used / Qty purchased x Purchase price)
Example: Bolognese pasta (serves 1):
Pasta 80g of 500g pack at £1.20: 80/500 x £1.20 = £0.19
Beef mince 150g of 500g at £4.50: 150/500 x £4.50 = £1.35
Tinned tomatoes 100g of 400g at £0.65: = £0.16
Onion, garlic, herbs, oil: £0.14
Total ingredient cost: £1.84
Food Cost Percentage
Food Cost % = (Cost per serving / Selling price) x 100
Industry benchmarks:
Fine dining: 25-35% | Casual: 28-35% | Cafes: 25-32%
Target 30% food cost on £1.84 cost:
Required price = £1.84 / 0.30 = £6.13 -> sell at £6.50-£7.00
Yield and Waste Adjustment
Yield % = Usable weight / Original weight x 100
Chicken breast (trimmed): ~90% yield
Fresh salmon fillet: ~75% yield
Onion (peeled): ~85% yield
Adjusted cost per usable kg:
Chicken at £6/kg, 90% yield: true cost = £6/0.90 = £6.67/kg
Failing to adjust yield undercosted every dish -- adds up to thousands per year.
Tracking Variance
Theoretical food cost (from recipes) vs Actual food cost (from invoices)
Variance = Actual % - Theoretical %
Acceptable: 0-2% | Concerning: 3-5% | Critical: 5%+
Monthly calculation:
Opening stock + Purchases - Closing stock = COGS
COGS / Revenue = Actual food cost %