Use the free Cat Litter Calculator below, right in your browser. No sign-up, no software to install, and nothing is sent to a server.
Cat litter is a regular cost that is easy to underestimate, because a bag that looks large can vanish in two weeks. The Cat Litter Calculator estimates how many kilos you need per month from the number of cats, the number of boxes, and the depth you keep, so buying in bulk becomes a plan instead of a guess.
The estimate starts from a simple rule of thumb: one cat at a standard depth of 5 cm uses about 7 kilos of litter per month, including scooping losses and top-ups. More cats scale the total directly, and deeper litter scales it too, because a box kept at 7.5 cm holds half as much again as the same box at 5 cm.
To use the tool, enter the cats, the boxes, and the depth in centimetres. The result gives kilos per month and a 3 month bulk quantity, plus a rough top-up per box. The per box figure helps when boxes sit in different rooms and you want to know how much to carry to each one.
Try the default example. Two cats with three boxes at 5 cm need about 14 kilos per month, or 42 kilos for three months. That is roughly two large bags a month, not one, and it explains why a single bag rarely covers a multi-cat home for a full month.
Depth is a trade-off, not just a cost. Too shallow, and urine reaches the base, sticks, and smells, which puts cats off the box. Too deep, and kittens and arthritic cats struggle to climb in, while you pay for litter that is never used. Most cats do well at 5 to 7 cm, with clumping litter at the lower end and non-clumping at the higher end.
Litter type changes the real usage, even at the same depth. Clumping litter lets you remove only the soiled parts, so a bag stretches further. Non-clumping litter is fully changed more often, so usage runs higher. Lightweight litter weighs less per bag but not per volume, so compare by litres or by days per bag, not by bag weight alone.
Scooping daily is the habit that saves litter and keeps cats happy. A box scooped once a day stays usable for longer, because soiled litter does not spread through the clean litter. Top up after scooping to restore the depth, and the monthly total in the tool already allows for those top-ups.
Buying in bulk suits the 3 month figure, but storage matters. Keep litter dry, sealed, and off cold floors, where bags can absorb damp and clump in the bag. A damp bag that clumps early is wasted money, so a dry cupboard beats a garage corner for storage, even if the garage has more space.
If the tool estimate feels high compared with your real use, check two things first. A covered box with a flap keeps more litter inside, while an open box near a busy door can scatter a surprising amount onto the floor. Litter mats and a lower entry lip cut tracking, and tracked litter is litter you bought but the cat never used.
Use the calculator when the household changes: a new kitten, an extra box, or a deeper fill all change the monthly total at once. With a known monthly figure, subscriptions and bulk orders stop running out early, and the litter bill becomes one more predictable part of keeping cats.
Smell control starts with scooping, not with scented litter or extra depth. A box scooped daily and topped up to a steady depth smells far less than a deep box left for days, because urine and solids are removed before they break down. Wash the empty box monthly, since scratched plastic holds smell even under fresh litter, and keep the box in a ventilated spot rather than a sealed cupboard. If smell persists despite daily scooping, the litter type or the box itself may be the problem, not the amount you buy.
Versión en español: Calculadora de arena para gatos – Kilos mensuales según gatos y areneros