How to Calculate Food Cost Per Portion in Your Restaurant

A menu price can look healthy while a dish quietly loses margin: the supplier pack size changed, the recipe uses a different quantity than you thought, or trim and waste never made it into the calculation. To calculate food cost per portion, cost every ingredient used in one serving, add those costs, then compare the total with the selling price.

This guide walks through that calculation with a simple example, explains how to handle pack sizes and yield, and shows where dish-level food cost ends and your overall monthly COGS begins.

What food cost per portion tells you

Food cost per portion is the ingredient cost of making one sellable serving of a dish. It helps answer practical menu questions: What does this plate cost to make? How much of its selling price goes to ingredients? What happens when one supplier price changes?

It is not the same as total restaurant profitability. A plate-cost calculation does not include labor, rent, utilities, payment fees, or other overhead. Keep those in your wider profit-and-loss view rather than treating ingredient margin as net profit.

How to calculate food cost per portion

1. Write down the standard recipe. List every ingredient in one batch, with the amount actually used. Include sauces, garnishes, cooking oil, and accompaniments when they are part of the serving.
2. Find the cost per usable unit. Use the invoice price and the pack quantity. If a 5-pound case costs $25, the purchase cost is $5 per pound before any measured trim or prep loss.
3. Cost the quantity used. Multiply each recipe quantity by that ingredient's unit cost.
4. Add the ingredient lines. The sum is the batch ingredient cost.
5. Divide by sellable portions. If the batch costs $48 and produces 12 portions, the ingredient cost is $4 per portion.

Formula: ingredient cost per portion = total ingredient cost for the batch ÷ sellable portions per batch.

Worked example: a burger

These figures are illustrative only—not a recommended price or industry benchmark. Suppose one burger serving uses:

• Bun: $0.70
• Patty: $2.40
• Cheese: $0.35
• Vegetables: $0.45
• Sauce: $0.20

Add the ingredient lines: $0.70 + $2.40 + $0.35 + $0.45 + $0.20 = $4.10 ingredient cost per burger.

If the menu price is $14, the dish-level food-cost percentage is: $4.10 ÷ $14 × 100 = 29.3%. The other $9.90 is the dish’s gross profit dollars before other costs—not net profit. Labor, rent, utilities, payment fees, and other operating expenses still have to be paid.

How to handle pack sizes, units, and usable yield

Match the recipe unit to the purchase unit before multiplying. If an invoice lists a 5-pound case but the recipe uses ounces, convert the pack price to a per-ounce cost first. Keep units consistent; do not multiply a per-pound price by a recipe quantity recorded in ounces.

Purchase price is not always the same as usable ingredient cost. If you measure that a $2.00 purchase yields 0.80 kg of usable product after trimming, the usable cost is $2.00 ÷ 0.80 = $2.50 per usable kg. Use your own measured yield where possible. If you have not measured it, label the estimate clearly instead of treating a guess as an exact cost.

Also record the date and supplier for each price. When a pack size or invoice price changes, update the ingredient price once and recalculate every recipe that uses it.

Dish-level food cost versus monthly COGS

Recipe costing gives you a theoretical ingredient cost for a dish made to its standard recipe. Overall food cost for a period uses inventory and purchases: opening inventory + purchases − closing inventory = food COGS. Divide that COGS by food sales and multiply by 100 to get the period’s overall food-cost percentage. Restaurant365 describes this inventory-based calculation in its food-cost calculation guide.

The two views answer different questions. Per-portion costing helps you price and compare menu items. Period COGS reflects what the kitchen actually used and purchased, including waste, over-portioning, spoilage, or counting differences. If they diverge, check the recipe quantities, purchase prices, inventory counts, and prep waste before changing menu prices.

Fixed costs and variable costs: what changes with sales?

After calculating gross profit, the next question is what it takes to keep the restaurant running. Fixed and variable describe how a cost behaves as activity changes; they are not a substitute for classifying a cost as direct COGS or an operating expense. The accounting treatment can depend on the business and reporting method, so use these as practical planning categories and confirm formal reporting with your accountant.

Fixed costs

A fixed cost generally stays about the same in total over a period, even when sales or covers rise or fall, within the relevant range. Rent is a common example. A monthly software subscription may also be fixed. “Fixed” does not mean the amount can never change: rent can reset, insurance can renew, and a lease can end.

Variable costs

A variable cost generally rises or falls with activity. Food ingredients used in dishes are a clear restaurant example: if you serve more portions, you typically use more ingredients. Card-processing fees may also vary with sales volume. For a menu decision, recipe ingredients are direct costs of the dish; rent is usually an overhead rather than a plate ingredient.

Some costs are mixed

A utility bill, for example, can include a fixed service charge plus usage that changes with activity. If a bill behaves this way, split the parts when you have the information; otherwise record your estimate and label it as an estimate.

Follow the numbers from sales to profit

1. Sales revenue − COGS = gross profit. COGS is the cost assigned to the goods sold under your accounting method. For a simple dish-level view, menu price minus ingredient cost gives a gross contribution before overhead; it is not net profit.
2. Gross profit − operating expenses = operating profit. Operating expenses may include rent, wages, utilities, marketing, and administration, depending on how your accounts classify each cost.
3. Then account for other items. Interest, taxes, depreciation, and other non-operating items can affect net income. Your accountant or bookkeeping system should define the exact P&L labels used for your business.

For break-even planning, separate costs by how they behave and use contribution margin—the selling price left after variable costs—to estimate how much sales activity is needed to cover fixed costs. Do not treat food-cost percentage by itself as a profit measure.

For a plain-English explanation of fixed, variable, and mixed costs—and how they fit into break-even planning—read our restaurant fixed and variable costs guide.

Turn the calculation into a repeatable routine

• Keep one standardized recipe per dish, with clear portion quantities.
• Update ingredient prices from invoices and note when they were checked.
• Recalculate when a supplier changes price, pack size, recipe, or portion.
• Review dish food cost alongside the dollar margin and sales volume; a percentage alone does not decide whether a dish belongs on the menu.
• Track monthly COGS separately from recipe-level estimates.

If maintaining those calculations is the part that slips during service, the Restaurant AI OS Toolkit includes recipe- and food-costing prompts plus a Numbers spreadsheet designed to recalculate linked dish costs when an ingredient price changes. You can also browse the 14 modules to see what else is included.

Common questions

How do I calculate food cost percentage for one dish?

Divide that serving’s ingredient cost by its menu price, then multiply by 100. For example, $4.10 ÷ $14 × 100 = 29.3%.

Does food cost per portion include labor and rent?

No. It is the ingredient cost for a serving. Labor, rent, utilities, and other overhead belong in your broader operating-cost and profit analysis.

How often should I update ingredient costs?

Update them when invoices, pack sizes, or suppliers change, and review your recipe costs regularly. The right review cadence depends on how quickly your inputs change and how often you update your menu.

A recipe cost is only useful when it reflects what you actually buy and serve. Start with one dish, check every ingredient line, and make the next menu decision from numbers you can explain.