Calculate food waste percentage, allowable waste, or starting food and estimate usable yield, waste cost, annual loss, and reduction savings.

Divide discarded food by the original available food.

Compare the same food batch and measurement period. “Remaining” means not discarded; it does not certify edibility or food safety.

Optional costs and reduction

Optional. Blank omits cost estimates. Use one currency; changing the weight unit converts the price.

Optional. With cost, estimates a 365-day run rate assuming this period repeats.

Optional. Blank omits the scenario; 25% means one quarter less waste, with starting food unchanged.

Food Waste Percentage Formula

The following two example problems outline the steps and information needed to calculate the Food Waste Percentage.

FWP = FW / FP × 100

Variables:

  • FWP is the Food Waste Percentage (%)
  • FW is the food discarded (kg or lb) 
  • FP is the original food available (the same weight unit and period) 

To calculate a food waste percentage, divide the food discarded by the original food available, then multiply by 100.

How to Calculate Food Waste Percentage?

The following steps outline how to calculate the Food Waste Percentage.

  1. First, measure the food discarded (kg or lb). 
  2. Next, measure the original food available in the same unit and period. 
  3. Next, gather the formula from above: FWP = FW / FP * 100.
  4. Finally, calculate the Food Waste Percentage.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

food discarded (lb) = 10

original food available (lb) = 20

FWP = 10 / 20 × 100 = 50%. The remaining food is 10 lb (50%); this does not assess edibility or food safety.