A measured-use planning tool
Use your household’s own observations and package price to estimate bag life, recurring cost, and a refill date. No generic usage recommendation is used.
Calculator
Enter the amount your household actually uses in an average week.
Your own measured use is more useful than a generic average. It can change with litter type, cat count, box setup, scooping, and household practice. To compare litter types, measure each one separately rather than assuming equal use.
The next-package date assumes the same observed use and replacing the package when it is empty. It includes no shipping time or reserve buffer. Veterinary or behavior questions about unusual use belong with a veterinarian.
Weekly use divided by 7 gives daily use. Package amount divided by daily use gives days per package. If you already know how many days a package lasted, that observed duration is used directly. Daily cost is package price divided by package days.
Monthly and annual figures are averaged consumption costs, using 365.2425 days per year and 365.2425 ÷ 12 days per month. They are not a prediction of when you will pay for whole packages. The next-package date adds the estimated duration, rounded up to a whole day, to the opened date. Money is displayed to the nearest cent; calculations use unrounded values.
Other approaches include broad US household-cost estimates and a product-specific UK estimator. Their usage assumptions differ from this measured-use method.