Party Food Calculator
Calculate how much food and drink to buy for a party by guest count and duration.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
This is a planning scenario, not a catering standard. Food portions use fixed per-person estimates by meal style, event length and appetite. The alcohol setting estimates drink counts; the dietary-share input reports how many guests that percentage represents, but does not add extra portions or determine which alternatives to provide. Adjust for your menu and guests.
Worked example
calculated with the default values below
Number of guests 25 · Event length 4 h · Food style Appetisers and snacks · Alcohol served Moderate drinking · Guest appetite Average (1×) · Dietary restriction share 15 % Total servings needed 300 · Food weight 75.0 lb · Drinks needed 100 · Ice needed 18.8 lb · Guests represented by dietary share 4
General background references
Disclaimer
These calculators give general estimates. Sizing, pricing, availability and standards vary by brand, retailer and country, so treat the output as a starting point and confirm it against the seller's or authority's own figures.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
S = ceil(G m max(1, H ÷ 2) a); lb = 0.25 S; D = ceil(G d + { 0.5 G H, d = 0; 0, d ≠ 0 })
- G
- Guests
- H
- Duration (hours)
- m
- Base servings per person by meal type
- a
- Appetite factor (0.8 / 1 / 1.3)
- d
- Drinks per person (0 / 2 / 4 / 6)
- D
- Total drinks
Servings use preset counts per guest, event length and appetite; food weight assumes 0.25 lb per serving. Drink quantity follows the selected alcohol setting. dietaryGuestsEstimate = ceil(guests × dietary share). These are planning assumptions, not catering or nutrition standards.
Frequently asked questions
Does the dietary-share input change the food quantity?
No. It reports the estimated number of guests represented by the percentage you enter. It does not add portions, identify specific restrictions, or calculate alternative dishes. The serving and drink counts are adjustable planning assumptions.
How does party duration affect estimated servings?
The model starts with a servings-per-guest value for the chosen meal type and multiplies it by max(1, event hours ÷ 2) and an appetite factor. At defaults, appetizers use 6, four hours multiply by 2, and 25 guests yield 300 servings. The dietary percentage only appears in the note; it does not change the numerical total.