How PortionPal Calculates Food Quantities
Every estimate starts with a disclosed per-adult portion, converts children to adult equivalents, applies one appetite factor and one leftovers factor, then rounds the purchase amount to a practical package.
Core formula
Adult equivalents = adults + (children × 0.6). Base quantity = adult equivalents × the food’s base portion. The light, standard and hearty appetite multipliers are 0.85, 1.0 and 1.2. Optional leftover multipliers are 1.0, 1.1 and 1.25.
Raw weight, cooked yield and units
The calculator labels raw and cooked quantities separately. Pasta uses an estimated cooked weight of 2.25 times dry weight, rice uses 3 times dry weight, and the BBQ calculator assumes a 70% cooked yield. US and metric displays convert the same underlying quantity; changing units does not change the formula.
Event type and serving style
Event-specific calculators may distribute demand across appetizers, meals, sides or drinks. Buffets can require a defined service buffer, while plated service allows tighter counts. A multi-item menu must divide demand among dishes so a full portion is not assigned to every item.
Package rounding
The calculated quantity and purchase suggestion are separate. Purchase suggestions round upward to a practical package size only after the appetite and leftover adjustment. We do not add a new percentage at every rounding step.
Limits and food safety
These are planning estimates, not nutrition prescriptions. Recipes, age, culture, appetite, event duration, climate and service style can change real demand. Follow product instructions and current official food-safety guidance. For buffets, the FDA’s safe buffet guidance covers hot and cold holding and the two-hour rule.
Corrections and review
Calculator changes require a documented assumption and a test. If an estimate appears wrong, include the calculator URL, guest inputs, selected units and the result in a contact message. Last reviewed: 16 July 2026.