After testing dozens of automatic litter boxes, I can say it's been difficult to determine which is the best cat litter (or rather, if there is one). Most people will want to look for a low-tracking, clumping cat litter that's compatible with their litter box. But there are other factors to consider, like allergens, material, the litter box itself, and how you'll deal with the waste. After a year of testing litter boxes and scooping tons of cat litter, let me sift through (get it?) the options so you can determine the best type of cat litter for you and your furry friend.