Party Catering Food Portion Estimator

How to use

Estimate food to buy or prepare using adult and child guests, editable planning portions, menu splits, cooking yields, and a planning buffer.

Enter adult and child counts separately. Set the child serving factor, serving style, main and total side planning portions, and buffer. Name your menu items and make each group total exactly 100%. Edit every main’s cooking yield. Choose purchase rounding, optional extras and any prices, then Calculate Food. Results also update as inputs change. Copy Shopping List or use browser Print / Save PDF. Reset restores the visible planning examples and blank prices.

How catering quantity estimates work

Effective guest units = adults + children × child factor. Base cooked main weight = effective units × main planning portion. Base prepared side weight = effective units × total side planning portion. Add the planning buffer once to each base quantity. Multiply buffered totals by item shares, then divide each cooked main target by its yield fraction to estimate raw purchases. Optional shopping rounding happens last. No portion, split or yield is inferred from an event type.

Adults and children

Adults contribute one serving unit each. Children contribute the editable child factor, allowed from 0 to 1.5. For 40 adults and 10 children at 0.5, the estimate uses 45 adult-equivalent serving units but 50 actual guests. This is a quantity-planning assumption, not a nutritional recommendation. Actual headcount is used for cost per guest.

Buffet vs plated service

Buffet and plated are descriptive serving-style choices. This version keeps your entered portions, shares and yields when you change style and applies no style multiplier. Adjust the visible planning assumptions to suit your menu and how you intend to serve it; buffet service does not automatically add an unsupported percentage.

Planning portions

The starting examples are 8 oz cooked main and 6 oz total prepared sides per adult-equivalent serving unit. These are editable planning assumptions, not universal serving requirements. The side portion covers all sides together. Weight inputs accept oz, lb, g and kg; the selected unit applies to the numbers you enter. Metric selection keeps primary shopping results metric. Portions are allowed from zero to 10 lb equivalent per effective guest.

Splitting food across multiple mains

Two to six mains can share the cooked main total. Each has a plain-text name of up to 50 characters, a percentage and an editable cooking yield. The initial two-item split is even. A 60/40 split is an illustrative alternative: it assigns 60% and 40% of the buffered cooked total before raw-yield conversion. All shares must sum exactly to 100%; the tool never silently normalizes them.

Splitting side dishes

One to eight side dishes share the total prepared side weight. Initial shares are 33.33%, 33.33% and 33.34%, making exactly 100%. An illustrative 40/35/25 menu assigns those shares of the total, not three separate per-person portions. Adding an item starts it at 0%; removing an item preserves other shares. Use the explicit Split sides evenly button or edit percentages to restore a valid total.

Cooked vs raw weight

Cooked target weight is the usable food you intend to prepare. Raw purchase weight is the amount modeled before cooking and usable-yield losses. Mains use raw purchase = cooked target ÷ (yield percentage / 100). Sides and additional salad are finished/prepared weights; this version does not estimate their raw ingredient yields.

How cooking yield works

Cooking yield is the fraction of raw purchased weight remaining as usable cooked food. An illustrative 75% yield means 1 lb raw becomes 0.75 lb usable cooked. Each main starts with the visible editable 75% planning example. There are no meat-specific presets or universal yield claims. Preparation, cut, trimming and cooking method can change actual yield. Use your own appropriate yield assumption; values must be greater than zero and no more than 100%.

Planning buffer

The planning buffer is an editable 0–50%, initially 10%. Buffered weight = base weight × (1 + buffer / 100). It is applied exactly once to food quantities and extras. Guest units are not buffered. Raw-yield conversion and shopping rounding do not add another buffer. A planning buffer is not a promise of leftovers or sufficient food for every event.

Shopping-rounding quantities

With shopping rounding enabled, raw main purchases round UP to 0.25, 0.5 or 1 lb increments. The default is 0.5 lb, and metric displays show its equivalent. Exact modeled raw weight and cooked targets stay visible. For example, 19.8 lb becomes 20 lb and 13.2 lb becomes 13.5 lb. Rounding occurs after guest math, the buffer, menu splits and yield conversion. Prepared sides and salad retain modeled weight; rolls, desserts and non-alcoholic drinks round up to whole units. No drink packaging is invented.

If you are baking sourdough rolls, scale a separate sourdough dough batch using your planned count and an independently chosen dough mass per piece. Prepared-food weights are not raw dough weights, and the dough tool does not estimate baking losses.

Optional food-cost estimate

Prices are optional and all start blank. Enter a price per selected weight unit for mains, sides or additional salad, and per whole unit for rolls, desserts and non-alcoholic drinks. Main cost uses the raw shopping purchase quantity, including enabled purchase rounding. Side and salad cost uses prepared weight; count-based extras use rounded shopping counts. The total is labeled priced items only when some prices are missing. Cost per guest divides by adults + children, never adult-equivalent units. A zero headcount has no per-guest division. Currency changes the label only, not exchange rates. Tax, delivery, service, labor and equipment are excluded.

Worked examples

All five examples use the same engine as the shopping list. Portions, menu shares and yields are illustrative editable assumptions.

Assumptions and limitations

All defaults are editable planning examples. Guest counts allow whole numbers from 0 to 100,000 each, child factor 0–1.5, portions 0–10 lb equivalent, buffer 0–50%, shares 0–100%, yields greater than 0 to 100%, count-based extra portions 0–100 per effective guest, and prices 0–1,000,000 per selected unit. Zero guests produce zero quantities. Malformed, negative, nonfinite, excessive or invalid inputs suppress the shopping list, details and costs; copy and print are disabled. There are no event-type adjustments, automatic dietary counts, nutrition recommendations, food-safety instructions or alcohol calculations. Create a named vegetarian main and allocate its share manually if needed. Inputs remain in component memory with no browser storage, account, saved events, URL persistence, input analytics or network calculations.

Food quantities are planning estimates. Actual consumption and cooking yield vary by menu, preparation method, guest preferences, and event conditions.

FAQ

Sources

NIST supports defined mass conversions: 1 lb = 16 oz = 453.59237 g; 1 kg = 1000 g. USDA explains purchase-to-prepared yield concepts in its program-specific food buying guide. This calculator uses that concept only, without adopting child-nutrition meal patterns or source portion examples as universal party requirements. No endorsement is implied.

• NIST — mass conversion factors (opens in a new tab)
• NIST — exact international pound definition (footnote 22) (opens in a new tab)
• USDA Food Buying Guide — purchase and prepared-food yield concepts (opens in a new tab)