Turn adults, children and your actual menu into a practical food and serving-supplies plan—with every assumption visible and adjustable.
Choose the real service format, count guests and adjust only what matters.
2. Count your guests
Full portions
60% portions
3. Choose your food plan
Use our starting allowances or calculate from the dishes you will actually serve.
Adjust appetite, child portions, dietary allocation, buffer and product pack sizes.
Percentage of all guests
Share of an adult portion
Percentage of guests
Planning estimate only. Confirm supplier yields, recipes, allergies, dietary needs, storage and service temperatures before ordering.
The model converts children into adjustable adult-equivalent portions, applies the selected appetite and buffer, then multiplies each declared per-person allowance. Nothing is hidden behind a vague “industry standard”.
Adults + children × child factor.
Light, standard or generous adjustment.
Extra quantity for variation and seconds.
Food, trays and disposables rounded up.
Methodology and declared assumptions
Portions vary with menu composition, guest mix, event time and supplier yield. Suggested-plan values are practical starting allowances. In Build my menu mode, every result comes from the dish's per-guest allowance, eligible audience and optional supplier-pack yield. Appetite, child factor and buffer remain visible and adjustable in both modes.
Methodology last reviewed: .
The Food Standards Agency says buffet allergen information must be provided for each food item separately, not once for the buffet as a whole. Maintain recipe-level records and manage cross-contamination.
Read official FSA guidanceVenues, event planners, caterers, community groups and party guides can embed this tool free of charge. Help readers turn adult and child guest counts into transparent food quantities and serving-supply requirements without leaving your page. The attribution beneath it is appreciated and can be removed if editorial policy requires it.
Preview the embedded calculatorCiting the methodology?
Copy a ready-to-use source citation for an article, lesson or industry guide.
Yes. Choose Build my menu, add each real dish or drink, select who it serves, and enter pieces, portions, grams or millilitres per eligible guest. You can also enter the quantity in a supplier pack or case to calculate how many packs to buy.
There is no single quantity that suits every menu. This calculator uses declared planning allowances for main dishes, sides, salads, bread and desserts, then adjusts for children, appetite and your chosen buffer. You can see every assumption before using the result.
The standard setting counts each child as 60% of an adult portion. You can change that factor in Advanced settings when planning for older children, teenagers or a child-focused menu.
Yes. The default service buffer is 10%. You can select 0%, 5%, 10%, 15% or 20%. The calculator shows both adult-equivalent guests and the final planned equivalents so the adjustment is transparent.
The finger-food preset starts at eight savoury pieces for the first two hours and adds two pieces for every additional hour, plus two sweet pieces. Appetite, child portions and the selected buffer are then applied.
Yes. Enter the vegetarian or vegan percentage and relevant main, sandwich and savoury quantities are divided into standard and vegetarian allocations. Confirm individual dietary requirements and allergens directly with guests.
UK food businesses must provide allergen information for each buffet item separately, rather than for the buffet as a whole. The calculator estimates quantities only and does not replace recipe-level allergen records or safe food-handling procedures.
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