Portion Cost Calculator

Portion cost is the price of the one thing a plate actually gives a guest — the exact weight or volume that leaves the kitchen — worked back from what the whole pack cost you. It sits underneath every food-cost and prime-cost number, and it's the easiest one to get wrong when a pack size doesn't divide neatly into a portion.

The formula, in the open

• Cost per portion = pack price × (portion size ÷ pack size), with both sizes in the SAME unit (grams to grams, ml to ml).
• Portions per pack = ⌊pack size ÷ portion size⌋, rounded DOWN — a fraction of a portion isn't a portion, so the leftover stays leftover.

A worked example

A 5,000 g (5 kg) bag of rice costs ₹450. One portion is 180 g. Cost per portion = 450 × 180 ÷ 5,000 = 16.2, which rounds to ₹16. The same bag yields ⌊5,000 ÷ 180⌋ = 27 portions, with 140 g left in the bag.

What moves the number

The two levers are the pack price (what you pay a supplier) and the portion size (what the recipe actually specifies). Trim the portion to 170 g without changing anything else and the same ₹450 bag now costs 450 × 170 ÷ 5,000 = 15.3, which rounds to ₹15 per portion — a real ₹1 difference per plate, straight from the same arithmetic above. This calculator assumes the whole portion is usable as bought; if trimming or cooking loses some of it first, the yield and waste calculator carries the true cost the rest of the way.

Try it

Enter your own pack and portion below. The defaults are the worked example — replace them with yours.