Start with a week you recognize.
Enter your usual weekly grocery spending, excluding restaurant meals if restaurant meals do not belong in the estimate. For an irregular shopping schedule, add several weeks of purchases and divide by the number of weeks.
Try different estimates.
The food waste cost estimator starts at 10% only to demonstrate the arithmetic. The 10% starting value is not a claim about your household or an average. Try a few values to see the range, then keep a record if you want a more grounded estimate.
Use the result to choose one change.
The estimate treats every grocery dollar equally, but an unused ingredient may cost more or less than the rest of your basket. The estimate also assumes the same pattern for 52 weeks. Use the estimate to consider a habit, such as checking cupboards before shopping, rather than treating the result as money you will definitely save.
