Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Protein needed
49.7
pounds
Starch (lbs)
33.1
Vegetables (lbs)
33.1
Appetizer pieces
636
Water servings
212
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter adults.
- 2Enter children.
- 3Enter service style.
- 4Enter protein per adult (oz).
- 5Enter starch per adult (oz).
- 6Enter vegetables per adult (oz).
- 7Enter event length (hours).
- 8Read your protein needed on the right — it updates as you type.
- 9Hit Share to keep the scenario or send it to someone.
About this calculator
Standard catering portions per adult run about 6 oz of protein, 4 oz of starch, and 4 oz of vegetables for a plated dinner, with buffets running higher because guests serve themselves. This scales those to your guest list.
Worked example
Using the values the calculator loads with:
Inputs
- Adults: 100
- Children: 12
- Service style: Buffet (1.25×)
- Protein per adult: 6 oz
- Starch per adult: 4 oz
- Vegetables per adult: 4 oz
- Event length: 4 hours
Results
- Protein needed: 49.7
- Starch (lbs): 33.1
- Vegetables (lbs): 33.1
- Appetizer pieces: 636
- Water servings: 212
What each field means
Inputs
- Adults
- The adults used in the calculation. Starts at 100 so you have a working example on load.
- Children
- The children used in the calculation. Starts at 12 so you have a working example on load.
- Service style
- Pick the option that matches your situation — the maths changes per option. Choices: Plated (1.0×), Buffet (1.25×), Family style (1.35×).
- Protein per adult (oz)
- The protein per adult used in the calculation, measured in oz. Starts at 6 oz so you have a working example on load.
- Starch per adult (oz)
- The starch per adult used in the calculation, measured in oz. Starts at 4 oz so you have a working example on load.
- Vegetables per adult (oz)
- The vegetables per adult used in the calculation, measured in oz. Starts at 4 oz so you have a working example on load.
- Event length (hours)
- The event length used in the calculation, measured in hours. Starts at 4 hours so you have a working example on load.
Results
- Protein needed
- pounds
- Starch (lbs)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Vegetables (lbs)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Appetizer pieces
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Water servings
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why is buffet higher than plated?
Guests serve themselves generously and often return, so caterers plan roughly 20 to 30 percent more food than a portion-controlled plated service.
How many appetizers per person?
Four to six pieces per person for a cocktail hour before dinner, and ten to twelve if passed appetizers are the meal.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Catering Quantity Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/catering-quantity
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/catering-quantity" target="_blank" rel="noopener">Catering Quantity Calculator — RevenueLab</a> (2026).</p>
Source: [Catering Quantity Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/catering-quantity) (2026).