The short answer
Prices differ by store. Where two buttons show, compare both before you buy.
Up to 4 cats
Whisker Litter-Robot 4
Sifts waste away after each visit, shows your cat’s weight in the app, and is listed for up to 4 cats of at least 3 lb each.
Cats up to 33 lb
Neakasa M1 Plus
An open top with no hood, listed for up to 3 cats from 3.3 to 33 lb, with a 3.0 gal (11.2 L) waste bin and a Kitten Mode for kittens under 3.3 lb.
AI camera
PETLIBRO Luma
An AI camera watches the waste and can tell #1 from #2. It recognizes up to 10 cats and has an open top for cats up to 22 lb, per the listing.
$599.99 at PETLIBROPrice checked Nov 2, 2:35 pm ET; it can change.
Prices differ by store. Compare both before you buy.
Buy at PETLIBROSee Amazon priceNot sure which one fits your pets?
1 quick question, then only the robots that fit.
A self-cleaning litter box sifts out waste after your cat leaves, so there’s no daily scooping, just a drawer or bin to empty. We’ve lined up seven current US models on the specs their makers publish: how many cats and what weight each is listed for, how much waste it holds, open or enclosed design, and what the app tracks.
Side by side
| Model | Cat weight | Cats | Kittens | Waste storage | Design | Litter | Warranty |
|---|---|---|---|---|---|---|---|
| Whisker Litter-Robot 4 | 3 to 25 lb | Up to 4 | Automatic mode from 3 lb; semi-automatic under 3 lb | Not stated | Enclosed | Clumping clay; some silica crystals. Not plant-based, pellet or non-clumping | 1 year |
| PETKIT PuraMax 2 | 3.3 to 22 lb | Not stated | 6 months and older | 1.8 gal (7 L) sealed bin | Enclosed, 20.1 gal (76 L) interior | Not stated | Not stated |
| PETKIT Purobot Max Pro 2 | 3.3 to 22 lb | Camera recognizes up to 15 | Not for kittens under 3.3 lb | 2.1 gal (8 L), up to 17 days for one cat | Enclosed, entry about 10 in from the floor | Listed as compatible with all cat litters | Not stated |
| CATLINK Open-X | Not stated | Single-cat (listing title) | Not stated | 3.2 gal (12 L), up to 15 days for one cat | Open entrance | Not stated | 1 year |
| PETLIBRO Luma | 2.2 to 22 lb | Recognizes up to 10 | Turn off auto clean under 6 months or under 2.2 lb | 2.9 gal (11 L) sealed bin | Open top | Clumping, tofu or mixed. Not crystal, pine or ultra-fine | 2 years |
| PetSafe ScoopFree SmartSpin | Up to 25 lb | Not stated (“multi-cat”) | Not stated | 1.6 gal (6 L) drawer, up to 2 weeks | Rotating; entry 12 in from the floor | Any; premium clumping recommended | 1 year |
| Neakasa M1 Plus | 3.3 to 33 lb | Up to 3 | Kitten Mode (no auto clean) for kittens under 3.3 lb | 3.0 gal (11.2 L), 7 to 14 days | Open top | Clumping or scoopable. Not pellet, newspaper or non-clumping | See note |
Cat numbers, weights, waste storage and design come from each model’s amazon.com listing. Kitten guidance, litter types and warranties come from each maker’s US site where the listing doesn’t state them, as do figures the listings leave out: the Litter-Robot 4’s 25 lb maximum (Whisker), the Luma’s 2.2 lb minimum (PETLIBRO), the SmartSpin’s 6 L drawer (PetSafe), and the Max Pro 2’s cat weights and 15-cat recognition (PETKIT). Neakasa’s listing names a 2-year protection plan, while its US warranty page states a 1-year limited warranty, so check what comes with yours. The PuraMax 2, Max Pro 2, Open-X, Luma and M1 Plus listings describe sensors that watch for a cat, and the Luma’s says they pause cleaning. Where only metric is published, the US figure on this page is our conversion, rounded, with the published figure in brackets.
The seven
Whisker Litter-Robot 4
The Litter-Robot 4 sifts waste from clean litter after each use, so there’s no scooping. You just empty the drawer. The Whisker app shows waste and litter levels and your cat’s weight after each visit, and it’s listed for up to 4 cats, each at least 3 lb. For odor, it takes carbon filters or optional OdorTrap packs.
Suits: multi-cat homes that like keeping an eye on weight.
Worth knowing: check who sells it and what warranty comes with it before you buy.
PETKIT PuraMax 2
The PuraMax 2 has a roomy 20.1 gal (76 L) interior for cats from 3.3 to 22 lb, 7 infrared and 4 weight sensors, a sealed 1.8 gal (7 L) waste bin, and auto, manual, timer and empty modes in the app.
Suits: bigger cats and homes with more than one cat.
Worth knowing: the listing says not to put it on carpet or mats, and it isn’t for kittens under 6 months. It also needs 2.4GHz Wi-Fi.
PETKIT Purobot Max Pro 2
The Max Pro 2 is PETKIT’s camera model. An AI camera with a 210° view and night vision recognizes each cat as it comes in and records its visits, and the waste goes into an 8 L (2.1 gal) sealed bin that the listing says lasts up to 17 days for one cat. The entrance sits about 10 in from the floor, which PETKIT pitches at short-legged and older cats, and the listing gives 35 to 45 dB.
Suits: multi-cat homes that want to see who used the box, and cats that struggle with a high step.
Worth knowing: PETKIT lists it for cats from 3.3 to 22 lb and not for kittens under 3.3 lb. The listing says it works with all cat litters and with 2.4GHz or 5GHz Wi-Fi.
CATLINK Open-X
The Open-X keeps its entrance open with a 360° view, which may suit cats who are nervous of hooded boxes. Its 3.2 gal (12 L) drawer holds up to 15 days of waste for one cat, it’s listed at 30dB, and the app gives you per-cat reports. A 9-point safety system uses weight, infrared and anti-pinch protection.
Suits: timid cats and quiet homes.
Worth knowing: the 15-day figure is for one cat, so with more cats you’ll be emptying the drawer more often. The listing states a one-year warranty.
PETLIBRO Luma
The Luma adds an AI camera that watches the waste and can tell #1 from #2. It recognizes up to 10 cats, has an open top for cats up to 22 lb, and comes with a 2.9 gal (11 L) sealed bin and a 2-year warranty, per the listing. Visual, weight and infrared sensors pause cleaning when needed.
Suits: owners who want to keep an eye on their cat’s bathroom habits.
Worth knowing: AI analysis and video recordings need a subscription. The livestream is free, per the listing.
$599.99 at PETLIBROPrice checked Nov 2, 2:35 pm ET; it can change.
Prices differ by store. Compare both before you buy.
Buy at PETLIBROSee Amazon price Full specificationsPetSafe ScoopFree SmartSpin
The SmartSpin rotates to sift clumps into a sealed waste drawer, and the listing says it runs hands-free for up to 2 weeks. It’s listed for cats up to 25 lb and as multi-cat friendly, takes clumping or non-clumping litter (PetSafe recommends a premium clumping litter), and the PetSafe Pet Companion app shows weight updates and litter box use.
Suits: owners who want to keep the litter they already buy.
Worth knowing: the listing doesn’t state how many cats it suits (PetSafe gives the drawer as 1.6 gal (6 L)), the entry is 12 in from the floor, and the app needs 2.4GHz Wi-Fi.
Neakasa M1 Plus
The M1 Plus has an open top with no hood and is listed for up to 3 cats from 3.3 to 33 lb, with a Kitten Mode in the app for kittens under 3.3 lb. Its 3.0 gal (11.2 L) waste bin needs emptying every 7 to 14 days, per the listing, and a brush-strip seal handles odor without carbon packs. Six rotary infrared sensors and a limited bed rotation guard against pinching, and the app tells cats apart and tracks each one’s visits.
Suits: large cats and homes with up to 3 cats.
Worth knowing: it needs 2.4GHz Wi-Fi, and it measures 22 x 20 x 26 in, so check the space first. The listing gives a 2-year protection plan.
How to choose
- Cat size and number. Check the weight range and how many cats each box is listed for. The Neakasa M1 Plus lists cats from 3.3 to 33 lb; the Litter-Robot 4 lists up to 4 cats.
- Nervous cats. An open design such as the CATLINK Open-X, Neakasa M1 Plus or PETLIBRO Luma may be easier for them to accept than an enclosed box.
- Floor. Put litter boxes on a hard, level floor. The PuraMax 2 listing specifically warns against carpet and mats.
- How often you want to empty it. Bin sizes and the days makers quote vary a lot; see the table and the question below.
- Subscriptions. The PETLIBRO Luma needs one for AI waste analysis and recordings.
- Wi-Fi. Some models need 2.4GHz, so check your router.
Open or enclosed?
Enclosed boxes (the Litter-Robot 4, PuraMax 2 and Max Pro 2 here) keep litter and smell inside a globe or drum, and the cat walks into a hooded space. Open designs (the Neakasa M1 Plus, PETLIBRO Luma and CATLINK Open-X) have no hood, which can suit cats that won’t use a covered box and bigger cats that need headroom. The SmartSpin sits in between: a rotating bowl with a raised entry.
- Big cats: the M1 Plus is listed up to 33 lb, the Litter-Robot 4 and SmartSpin up to 25 lb, and the PuraMax 2, Max Pro 2 and Luma up to 22 lb.
- Small or older cats: check the entry height. The Max Pro 2’s entrance is about 10 in from the floor and the SmartSpin’s 12 in.
- Space: every one of these is far bigger than a plain litter tray. Measure the spot, including room to slide the drawer out.
Will it fit? Sizes and noise
Every self-cleaning box is much bigger than a plain tray. These are the sizes and noise levels each listing or maker publishes. Measure your spot and leave room to pull the drawer out. The SmartSpin has the smallest footprint here and the Litter-Robot 4 is the tallest, so check the height if it goes under a shelf or counter.
| Model | Size (L x W x H) | Noise |
|---|---|---|
| Whisker Litter-Robot 4 | 24 x 24 x 31 in (the listing also gives 27 x 24.25 x 29.5 in) | Not stated |
| PETKIT PuraMax 2 | 24.21 x 21.96 x 21.96 in | Not stated |
| PETKIT Purobot Max Pro 2 | 25.87 x 21.18 x 23.74 in | 35 to 45 dB |
| CATLINK Open-X | 23 x 21 x 23 in | 30 dB |
| PETLIBRO Luma | 23.3 x 22.5 x 28.1 in | 35 to 47 dB, depending on fan speed |
| PetSafe ScoopFree SmartSpin | 20.9 x 18.9 x 26.4 in | Not stated |
| Neakasa M1 Plus | 22 x 20 x 26 in | Not stated |
Sizes come from each model’s amazon.com listing (the Litter-Robot 4, PuraMax 2 and Open-X read Nov 1, 2026), except the Luma’s, which comes from petlibro.com (read Nov 1). Noise figures are the makers’ own, measured their own way, so treat them as a rough guide.
For more than one cat
Makers state the number of cats in different ways, so read the figure for what it is. The Litter-Robot 4 is listed for up to 4 cats and the M1 Plus for up to 3. The Luma’s 10 and the Max Pro 2’s 15 are how many cats the camera can tell apart, not how many the box can serve. PetSafe and PETKIT (PuraMax 2) say “multi-cat” without a number. CATLINK lists the Open-X version here as single-cat. More cats also means emptying sooner: CATLINK’s 15 days and PETKIT’s 17 days are for one cat.
Looking at the Litter-Robot 4? How the others differ
If you’re weighing the Litter-Robot 4 against the others, these are the differences the makers’ published specs show:
- Bigger cats. The Neakasa M1 Plus is listed for cats up to 33 lb, against 25 lb for the Litter-Robot 4.
- No hood. The M1 Plus, PETLIBRO Luma and CATLINK Open-X are open designs; the Litter-Robot 4 is enclosed.
- Camera. The Luma and the PETKIT Purobot Max Pro 2 have AI cameras that recognize each cat; the Litter-Robot 4 logs each cat’s weight in the app.
- Waste storage. The M1 Plus (3.0 gal), Open-X (3.2 gal) and Luma (2.9 gal) state their bin size; Whisker’s listing doesn’t.
- Warranty. PETLIBRO states 2 years for the Luma; Whisker states 1 year for the Litter-Robot 4.
- Litter. Whisker rules out plant-based and pellet litter for the Litter-Robot 4; PETKIT lists the Max Pro 2 as compatible with all cat litters.
Where the Litter-Robot 4 leads: it’s listed for up to 4 cats, the highest cat count any maker here states.
Are they worth it?
If daily scooping is the job you want gone, a self-cleaning box takes it over: it sifts after each visit, and you empty a sealed drawer or bin every few days to two weeks instead. What the makers themselves ask of you is worth weighing first:
- A hard, level floor. PETKIT says to avoid soft, uneven or unstable flooring, and Whisker says the Litter-Robot 4’s weight readings are most accurate on a firm surface.
- The right litter. Most want clumping litter. Whisker rules out plant-based, pellet and non-clumping litter for the Litter-Robot 4, and PETLIBRO rules out crystal and pine for the Luma.
- Wi-Fi. The app features need it, and several (Litter-Robot 4, SmartSpin, M1 Plus) want a 2.4GHz network.
- Ongoing costs. Liners, filters or odor packs, and on some models a subscription for camera recordings or AI analysis (PETLIBRO’s for the Luma).
- Kittens. Most have a minimum weight or age, below which you switch off automatic cleaning (see the table).
- Time to adjust. Some cats take a while to trust a moving box; see below.
Getting your cat to use it
Whisker suggests putting the new box where the old one was and keeping both nearby for a short time, mixing a cup of used litter into the new one, and leaving it switched off until your cat has tried it. PETKIT also says to keep the old box nearby at first, then move it away gradually, and to talk to your vet if your cat’s litter habits change suddenly. Neakasa recommends cleaning manually for the first few days with timid cats.
Questions
Are self-cleaning litter boxes worth it?
They save the daily scoop: you empty a sealed drawer every few days to two weeks instead. In return they need a hard floor, a litter the maker supports, Wi-Fi for the app, and some ongoing supplies. See “Are they worth it?” above for what each maker asks.
What are the downsides?
They’re large, they need power and usually Wi-Fi, most only take clumping litter, some features need a subscription, and kittens below each maker’s minimum weight or age shouldn’t use the automatic cycle. Some cats also need a few days or weeks to get used to one.
Are they safe for cats and kittens?
Most listings here describe sensors that detect a cat and pause or stop cleaning. For kittens, only above each maker’s limit. Whisker says kittens of at least 3 lb can use the Litter-Robot 4 in automatic mode. PETLIBRO says to turn off auto clean on the Luma for cats under 6 months or under 2.2 lb. PETKIT lists the PuraMax 2 for cats 6 months and older and the Max Pro 2 not for kittens under 3.3 lb. The M1 Plus has a Kitten Mode with no automatic cleaning.
Do any need a subscription?
The PETLIBRO Luma needs one for AI waste analysis and recordings. Its livestream is free.
Is there one that cleans itself with water?
Yes, the CatGenie washes reusable granules instead of using litter and flushes waste down a drain. CatGenie says it needs a cold-water line, a drain and power. It isn’t in this comparison.
Related
Feeding on a schedule too? See our automatic pet feeders compared. Browse every model in litter boxes and pet feeders.
