Litter Robot 4 vs PetKit PuraMax 2
Litter robot 4 vs petkit puramax 2 is a choice between a $699 globe box rated for cats up to 25 lbs and a $399.99 drum box rated to 22 lbs. Over 3 years with one cat, the PuraMax 2 costs about $373 less including supplies.
Researched by Riley Hart · updated Oct 15, 2026 · How we research
Buy the Litter-Robot 4 if your cat is over 10 lbs, the box may sit on carpet, or you want the longer track record and parts network; it costs $699. Buy the PETKIT PuraMax 2 if your cats are small to medium, your floors are hard, and you want to spend less: about $662 over 3 years against about $1,035 for the Litter-Robot 4.
| Feature | Litter-Robot 4 | PETKIT PuraMax 2 |
|---|---|---|
| Price (Oct 15, 2026) | $699 at Whisker | $399.99 at PETKIT (our listed price); $479.99 at Chewy |
| Design | Rotating globe with sealed drawer | Hooded drum that rolls back and forth, entrance stays open |
| Cat weight range | 3 to 25 lb | 3.3 to 22 lb, cats 6 months and older |
| Max cats | Up to 4 | Not stated; app tracks each cat by weight |
| Entry | 15.75 in wide opening, 6.9 in step | Low entry; size not published for this model |
| Size and weight | 22 x 27 in footprint, 29.5 in tall, 24 lb | 24.4 x 21.2 x 21.7 in, 22 lb |
| Waste capacity | Drawer, about every 8 days for 1 cat | 7 L bin, up to 15 days for 1 cat |
| Safety sensors | Laser curtain and weight sensors, SafeCat | 12 sensors per PETKIT (Cats.com counted 11), anti pinch |
| Litter | Clumping clay recommended | Clumping clay, tofu, corn, bentonite; two sifters; not crystal |
| Noise | No dB rating published | 35 dB in maker specs, 45 dB in its FAQ |
| Carpet | Carpet Tray add on for accurate weight | Hard floors only per Cats.com and Chewy reviewers |
| Subscription | None needed; Whisker+ optional | None needed |
| Warranty | 1 year, 3 year plan $129, 90 day trial | 2 years per PETKIT product badge |
| 3 year supplies, 1 cat | $336 (filters $180, liners $156) | $261.77 (bags $21.89, N50 odor packs $239.88) |
| 3 year total with box | $1,035 | $661.76 at $399.99; $741.76 at Chewy's price |
Specs, prices and supply costs from our robot data, Whisker's comparison chart, PETKIT's product page and Chewy, checked October 15, 2026. The PETKIT store link for the PuraMax 2 now shows the newer Purobot Max 3 at $399.99, so check which model you are buying.
Price and 3 year cost
The Litter-Robot 4 costs $699 at Whisker as of October 15, 2026. Our listed price for the PuraMax 2 is $399.99 from the PETKIT store; Chewy lists it at $479.99 against a $499 list price.
Supplies narrow the gap a little. For one cat over 3 years, the Litter-Robot 4 needs about $180 of carbon filters (one $5 filter a month) and $156 of drawer liners (about one a week). The PuraMax 2 needs about $22 of bags at the maker's best case of one bag every 15 days, plus about $240 of N50 odor packs at one piece a month.
That puts the 3 year total at about $1,035 for the Litter-Robot 4 and about $662 for the PuraMax 2, or about $742 at Chewy's price. Owners report emptying the PETKIT bin every 5 to 10 days, so real bag use may be higher. Neither box needs a subscription.
Cat size and entry
This is the clearest difference. Whisker rates the Litter-Robot 4 for cats from 3 to 25 lbs with a 15.75 inch globe opening. PETKIT rates the PuraMax 2 for cats from 3.3 to 22 lbs.
Cats.com found that its cats over ten pounds ignored the PuraMax 2, and quoted a customer whose cat did not fit and went outside the box. Cats.com's roundup says the PuraMax 2 may not suit larger cats. It also says some owners find the Litter-Robot 4 cramped for large cats, so for a cat near 25 lbs, look at the Litter-Robot 5 instead.
Litter, floors and setup
The PuraMax 2 is more flexible on litter. It ships with two sifters and takes clumping clay, tofu, corn and bentonite litters, but not crystal. Whisker recommends clumping clay for the Litter-Robot 4, and Cats.com says tofu litter will not work in it.
The Litter-Robot 4 handles carpet better. Whisker sells a Carpet Tray so the scale reads accurately. Cats.com says the PuraMax 2 is designed for hard floors, and Chewy reviewers report its sensors do not register weight at all on carpet.
Footprints are similar. The Litter-Robot 4 needs 22 by 27 inches and stands 29.5 inches tall. The PuraMax 2 measures 24.4 by 21.2 by 21.7 inches, so it fits under more shelves.
What reviewers found: Litter-Robot 4
- Cats.com named it Runner Up in its October 2026 roundup and called it one of the most reliable automatic boxes, noting early sensor faults were largely fixed by firmware and app updates.
- CNN Underscored emptied the drawer about once a week with two cats, found it quieter than the Litter-Robot 3, and said the cats adjusted in about a week.
- The Irish Times found it quiet with no smells and a clean tray. The sensors stopped the drum when a kitten jumped in mid cycle. App cat ID by weight was less reliable for cats of similar size.
- Common complaints: it is bulky, it is expensive, and litter scatter from playful cats.
What reviewers found: PETKIT PuraMax 2
- Cats.com scored it 3.8 out of 5 and named it Best Odor Control in its October 2026 roundup. The sealed drawer and leakproof liner held up even when a cat urinated at the back.
- Deep cleaning was the weak point. Cats.com found the magnetic litter remover worked poorly, emptying was slow and left litter behind.
- Chewy rates it 4.1 out of 5. Some reviewers call it quiet; one said their cats took two months to adjust, others one to two weeks.
- Cats.com noted customer reports of urine leaks, sensor faults and a small tray.
PuraMax 2 or its successor?
PETKIT's US store link for the PuraMax 2 now opens the Purobot Max 3 (model P9906), also at $399.99. Coolcuration, which used a PuraMax 2 for two years, calls the Max 3 a refinement with a 43% larger entry and a side mounted 7 L bin. Chewy still sells the PuraMax 2. Confirm the model name before you buy, since specs and reviews differ.
Which to buy
Pick the Litter-Robot 4 for cats over 10 lbs, multi cat homes up to 4 cats, carpeted rooms, or if you value a long track record and easy parts. Its 90 day trial lowers the risk.
Pick the PuraMax 2 for small to medium cats on hard floors, if you use tofu or corn litter, or if you want to spend about $370 less over 3 years.
Full profiles with 3 year cost
Questions people ask
Is the Litter-Robot 4 better than the PETKIT PuraMax 2?
For larger cats and carpet, yes: it is rated to 25 lbs against 22 lbs and has a carpet tray option. The PuraMax 2 is cheaper, about $662 over 3 years against about $1,035, and takes more litter types.
Does the PETKIT PuraMax 2 work for big cats?
PETKIT rates it to 22 lbs. Cats.com found its cats over ten pounds ignored it and does not recommend it for larger cats.
Can you use the PuraMax 2 on carpet?
Cats.com says it is designed for hard floors, and Chewy reviewers report its weight sensor does not register on carpet. The Litter-Robot 4 has an add on Carpet Tray.
Do either need a subscription?
No. Both clean and track cats without a paid plan. Whisker+ for the Litter-Robot 4 is optional at $7.99 a month or $79.90 a year.
Which is quieter?
Whisker publishes no dB rating for the Litter-Robot 4; reviewers describe it as quiet. PETKIT lists 35 dB for the PuraMax 2 in its specs but 45 dB in its FAQ.
Related
- Best self cleaning litter boxes, ranked
- Litter-Robot 4 vs 5
- How to choose a self cleaning litter box
- Litter-Robot Black Friday deals
- Litter-Robot 4 profile
- PETKIT PuraMax 2 profile
Sources
- Whisker: Litter-Robot comparison chart
- PETKIT: PuraMax 2 product link (now shows Purobot Max 3)
- Chewy: PETKIT PuraMax 2
- Cats.com: PETKIT PuraMax 2 review
- Cats.com: Best automatic litter boxes (updated October 2026)
- CNN Underscored: Litter-Robot 4 review
- The Irish Times: Litter Robot 4 review
- Coolcuration: PETKIT Purobot Max 3 review