Formula
days_per_package = package_weight_lb / monthly_lbs_used * 30.44
Litter usage model
How long does cat litter last?
Litter duration depends on package weight, number of cats, litter type, box setup, and how often the box is fully refreshed. CatCost starts with pounds used per month so the estimate can connect directly to price per pound.
Package lbStart with usable weight
Cat countScale by household size
Days leftWeight divided by monthly use
| Household | Planning assumption | 20 lb package | 40 lb package | Cost metric |
|---|---|---|---|---|
| One cat | 12-16 lb per month | About 5-7 weeks | About 10-13 weeks | $/lb |
| Two cats | 22-30 lb per month | About 3-4 weeks | About 5-7 weeks | $/lb and monthly cost |
| Three cats | 32-44 lb per month | About 2-3 weeks | About 4-5 weeks | Monthly cost |
What price per pound misses
Price per pound does not capture dust, tracking, odor control, clumping quality, or how often a litter needs to be fully replaced.
Sources and methodology
- Litter Box ProblemsASPCA. Used for litter box planning context, including the one-box-per-cat-plus-one guideline.