Dietary Buffet Calculator

If you do not have specific RSVP data, common UK estimates are: 10-15% vegetarian, 3-5% vegan, 5-8% gluten-free, and 3-5% dairy-free. For younger demographics, vegetarian and vegan percentages tend to be higher. Always ask guests about their dietary needs when possible.

No. Many guests without specific dietary requirements will also choose vegetarian or vegan options if they look appealing. This calculator accounts for the food needed for each dietary group, but consider that some dishes can serve multiple groups — a vegan dish is also vegetarian and dairy-free.

Aim for at least 2-3 naturally gluten-free dishes for a standard buffet. Rice dishes, salads, fruit platters, and many meat dishes are naturally gluten-free. Label everything clearly so guests with dietary requirements can easily identify suitable options. If any guest is coeliac, prepare gluten-free items separately to avoid cross-contamination.

The variety factor adds a buffer to account for uneven consumption across dishes. A factor of 1.15 means preparing 15% more than the mathematical minimum, which matches the common catering rule of thumb of over-catering by about 10-15% so no single popular dish runs out early. Raise it for guests with strong preferences, or lower it to trim waste.

The default is 300 g per person, in line with UK finger-buffet guidance of roughly 250 g of savoury food plus around 50 g of something sweet — about half a pound to a pound (227-454 g) per head when the buffet is the main offering. That base is calibrated to a 2-hour event. Because guests graze more the longer they stay, the calculator adjusts the base by about 15% per hour around that 2-hour point: a 3-hour event uses 15% more, a 4-hour event 30% more, and a 1-hour reception 15% less. These are planning heuristics rather than fixed standards, so adjust the base amount in Advanced Options to suit your menu.