Cat Litter Calculator

Cat Litter Guide

How Many Litter Boxes?

The golden rule: one litter box per cat, plus one extra. Two cats need at least three boxes. Boxes should be placed in different locations — cats prefer not to use a box another cat has just used, and placing all boxes in one room is functionally equivalent to having fewer boxes. A minimum box size is 1.5× the length of the cat from nose to tail base. Most commercial boxes are too small for large cats.

Clumping vs Non-Clumping

Clumping litter (clay, tofu, or corn-based) forms solid clumps when wet, allowing targeted removal without changing all the litter. A 5kg bag of good clumping litter lasts approximately 2–4 weeks for one cat with daily scooping. Non-clumping (wood pellets, paper) requires full replacement more often but some are more environmentally friendly and dust-free. Silica crystal gel absorbs moisture and odour effectively and lasts longer but some cats dislike the texture.

Hygiene and Health

Dirty litter boxes are the leading cause of litter box avoidance, which leads to inappropriate elimination (urinating outside the box). Scoop at least once daily, twice if possible. Do a full litter change and box wash with mild unscented soap every 2–4 weeks for clumping litter, weekly for non-clumping. Avoid strongly scented litters — cats' sense of smell is 14 times stronger than humans' and heavy perfumes are off-putting. Unscented litters with activated carbon control odour more effectively.

Monitoring Health Through Litter Use

The litter box is an important health monitoring tool. Watch for: increased frequency of urination (possible diabetes or kidney disease), straining without producing urine (urinary blockage — a veterinary emergency, especially in male cats), blood in urine, abnormally large or small clumps, or significant changes in odour or output volume. Male cats in particular are prone to urinary blockages — if a male cat is visiting the box repeatedly without producing urine, seek emergency veterinary care