How to measure for a litter box enclosure — a four-minute guide with a tape

Number 1: your pan's footprint, plus two inches a side

Measure the widest points of your litter pan, not the base. Most pans flare, so the top rim is two to three inches wider than the bottom, and the rim is what has to clear the cabinet walls. Write down length and width in inches.

Then add two inches to each side. That clearance is not decoration: it is the room you need to lift the pan out at an angle, to slide a litter mat alongside it, and to stop the pan wedging against a wall panel that has swollen slightly in a humid month. A pan measuring 17.5 by 20 inches therefore wants an interior of about 21.5 by 24 inches — which is larger than several cabinets sold specifically to hold it.

For reference, here are four common boxes with the dimensions their own manufacturers publish:

Number 2: height, plus headroom the cat can stand in

For an open pan, measure from the floor to the top of the rim and add at least eight inches of clear air above it. Ohio State's Indoor Pet Initiative sets the standard for the box itself — as a rule the litter box should be large enough for your cat to stand up on all fours and turn around in — and inside a cabinet that rule applies to the cabinet, because the cabinet is now the box's ceiling.

For a hooded pan, the hood height is your number: a 16.5-inch hood needs an interior of at least 17 inches before the lid can be lifted at all, and more if you want to take the hood off without removing the whole unit from the cupboard. This is why so many cabinets with an 18-inch interior height are, in practice, open-pan-only.

Cabinet interiors in this category cluster between 17.6 and 19 inches of height. If your pan plus headroom exceeds that, you are shopping for a taller cabinet, not a nicer one.

Number 3: the doorway, measured against your actual cat

This is the number brands hide and buyers forget. Measure your cat's shoulder height while it is standing — floor to the top of the shoulder blades — and its chest width at the widest point. A cat will fold through a hole smaller than that; the question is whether it will keep choosing to.

Published doorways vary enormously. Yaheetech publishes a 6.5 by 8-inch opening on its 19-inch side-table cabinet and a 10.6-inch-high cat hole on a larger model. Most other brands, including Feandrea and Hzuaneri, publish no opening dimension at all, which means you are measuring it on arrival with the return window running.

Two rules of thumb from the guidance, not from marketing: Cornell's Feline Health Center notes that larger cats need bigger boxes, and that kittens and elderly cats need low sides — a high threshold at the doorway is the same obstacle as a high box wall. And if your cat pauses at the opening rather than walking straight through, the doorway is too small, whatever the tape says.

Interior dimensions of the cabinets we recommend

Every figure below is quoted from the manufacturer's own page. Compare these to your three numbers before you compare anything else.

The dividers are structural — read the small print

Several cabinets get their large interior only when you remove an internal panel, and that panel is holding the top up. Feandrea states it plainly on its own page: with the divider in place the top is rated to 132 lb, and with it removed that rating falls to 22 lb. Decide which cabinet you are building before you assemble it, because a 22 lb top is a plant and a photo frame, not a lamp, a stack of books and a cat.

Where it goes matters as much as what fits

The ASPCA's placement guidance is worth taking literally in a small home: put boxes in accessible locations away from high-traffic areas and away from anywhere a cat could feel trapped, keep them away from loud appliances such as a washer and dryer, and do not put the food bowls next to the box. It also recommends one box per cat plus one extra, and a box on each level in a multistory home.

In a one-bedroom apartment that usually resolves to one enclosure somewhere the household walks past but does not sit, and a second box — often a plain open pan — somewhere quieter. That second box is also your insurance policy if the cat turns out to dislike the enclosure.

If you use a self-cleaning box

Measure the machine, not the pan, and include the height of its travel. A Litter-Robot 4 has a published footprint of 22 by 27 inches and stands 29.5 inches high with a 15.75-inch square entryway. No cabinet interior in our guide comes close, so the honest answer for that machine is a cabinet built and sold specifically for self-cleaning boxes — and at the time of writing the only one we found that advertises the fit publishes no dimensions at all, which makes it unbuyable on evidence.

One more number nobody prints: replacement interval

Petmate recommends replacing a cat's litter box every 12 months, on the grounds that odours penetrate plastic and resins over time. Whether or not you follow that schedule, it is a useful reminder that the pan inside a beautiful cabinet is a consumable — and that a cabinet whose interior only just fits today's pan will not fit the slightly larger one you buy next year.

The four-minute checklist

1. Pan footprint at the widest point, plus two inches each side. That is your minimum interior length and width.
2. Pan height plus eight inches of headroom, or the full hood height plus lifting room. That is your minimum interior height.
3. Cat's shoulder height and chest width. Compare against the published doorway; if the brand publishes none, decide whether you are willing to find out on arrival.
4. Check the load rating you will actually have — with or without the divider you plan to remove.
5. Measure the spot in the room, including the door swing. A 31.5-inch cabinet with barn doors needs clearance in front of it that a 19-inch side table does not.

Take those numbers to the hidden litter box furniture guide, where every pick lists its published interior, or to the enclosed versus open comparison if you are still deciding whether to cover the box at all.