Quick answer

Choose a pan at least 1.5 times your cat's body length, measured from nose to the base of the tail. For most adult cats that means a pan roughly 24 inches long; for Maine Coons, Ragdolls, Savannahs, or multi-cat homes, start at 30 inches. Then pick the entry style: open top for easy access, high sided for scatter control, or top entry for the least tracking.

Measure your cat before you shop

Measure twice: body length from nose to tail base, and standing height from floor to shoulder. A cat should be able to turn around, dig, and squat without touching the walls. If your cat's nose-to-tail-base length is 18 inches, a 27-inch pan gives comfortable clearance; a 20-inch pan leaves almost no turning room.

Height matters too. Kittens and senior cats often struggle to step over tall walls, so a lower entry is easier on joints. Large breeds and cats that spray need taller walls to keep urine inside the pan.

Match pan dimensions to your cat and your home

A large cat litter box needs length and width, not just height. A 30"L x 20"W x 14"H pan gives a big cat room to stretch and dig, and it also works for two cats sharing one box. A smaller 20-inch pan suits kittens and petite adults but forces larger cats to hang over the edge.

Check the floor space where the box will sit before ordering. A 30-inch pan needs about 2.5 feet of clearance in front for entry and scooping. Corner placement can hide the box, but leave enough room for the lid or shield to open or lift.

Choose the entry style that fits your cat

Open top litter pans are the easiest for cats to use and the simplest to scoop. High sided litter pans add walls that act as a scatter shield, keeping litter and spray inside without a hood. Top entry designs trade a little entry effort for the best litter containment, because cats jump out onto a grooved lid that catches granules from their paws.

If your cat is a digger or a high urinator, a high sided or top entry box saves daily cleanup. If your cat is elderly, pregnant, or new to the home, start with an open top pan and add a high sided pan later if scatter becomes a problem.

Plan for litter type, scooping, and replacement

Clumping clay litter works in any of these pans, but a smooth interior with minimal crevices makes scooping faster and reduces odor buildup. Deep pans hold more litter, so you scoop less often but use more litter per change. Shallow pans are easier for kittens but need more frequent full changes.

Buy one pan per cat plus one extra, and place them in separate areas if you have the room. If space is tight, a single XX-large pan can serve two cats, but you will need to scoop at least twice a day.

Decision rules for choosing a litter box size

  • If your cat is under 12 inches nose to tail base: Choose a pan at least 20 inches long with low walls. Kittens and small adults can step in easily, and a smaller pan takes less floor space. Recheck size at 6 months; most cats outgrow kitten pans quickly.
  • If your cat is 12 to 18 inches nose to tail base: Choose a pan 24 to 27 inches long. A high sided litter pan with a scatter shield controls litter without making entry hard. Measure your cat, not the box, before ordering.
  • If your cat is over 18 inches or you have multiple cats: Choose a pan at least 30 inches long. The XX-Large Side Entry Cat Litter Box gives large breeds and multi-cat homes the turning and digging room they need. One pan per cat plus one extra is the baseline; a single XX-large pan is the fallback when space is tight.
  • If litter tracking is your main complaint: Choose a top entry box with a grooved lid. Cats jump out onto the lid, which catches granules before they reach the floor. Top entry works best for agile adult cats, not seniors or kittens.
  • If your cat is a senior or has mobility issues: Choose an open top pan with a low entry. High walls and top entry designs can be painful for cats with arthritis. Pair a low-entry pan with a nearby mat to catch stray litter.

Product facts that matter for sizing

  • XX-Large Side Entry Cat Litter Box, Navy: XX-Large Side Entry Cat Litter Box, Navy: 30"L x 20"W x 14"H, made for large and extra-large breeds like Maine Coons, Ragdolls, and Savannahs, and a good choice for multi-cat households or older cats that need extra space. This is the pan to choose when your cat measures 18 inches or more nose to tail base, or when two cats share one box. The 30-inch length gives turning and digging room that a standard pan cannot.
  • Large Cat Litter Box with Scatter Shield and Scoop, Open Top High Sided Cat Litter Pan, Blue: Large Cat Litter Box with Scatter Shield and Scoop, Blue: open top design with tall walls that form a scatter shield, keeping litter and spray inside while keeping entry easy. The open top keeps access simple for cats that refuse hooded boxes, while the tall walls control scatter. It is a middle ground between a plain open pan and a top entry box.
  • Top Entry Cat Litter Box, Black/Light Gray: Top Entry Cat Litter Box, Black/Light Gray: large top entryway, grooved lid to remove litter particles from paws, rounded shape with included scoop, 20.8"L x 16.1"W x 14.6"H. Best for cats that track litter across the floor. The grooved lid catches granules, but the 20.8-inch length is tighter than the XX-large pan, so measure your cat before choosing this style.

Who each litter box size is best for

Best for

  • Large breeds like Maine Coons, Ragdolls, and Savannahs that need a 30-inch pan
  • Multi-cat households sharing one or two boxes
  • Cats that spray or dig, which need high walls or a scatter shield
  • Owners who want less litter tracking and are willing to scoop a top entry box

Not for

  • Kittens under 6 months that cannot jump into a top entry box
  • Senior cats with arthritis that need a low, open entry
  • Homes with less than 2.5 feet of clearance in front of the box
  • Owners who want a hooded box; these pans are open or top entry only