PETKIT Purobot Ultra vs Litter-Robot 5: Self-Bagging Camera Box or Big-Cat Globe?

The Litter-Robot 5 is the better flagship for most homes, and the PETKIT Purobot Ultra is the better gadget. In the PETKIT Purobot Ultra vs Litter-Robot 5 matchup, the two cost about the same, roughly $800. The Whisker globe is rated for five cats and 30 lb, while the PETKIT drum seals its own waste bags and films every visit.

We haven’t tested either box ourselves. This comparison uses maker specs from Whisker, Amazon listing text and WIRED’s reporting, which we name wherever a test result appears. Prices are typical street prices from dated sources, not live Amazon prices, so check today’s price before you buy.

PETKIT Purobot Ultra vs Litter-Robot 5 at a glance

Every other box we track is in the comparison chart.

Cat size and cat count decide the winner

The Litter-Robot 5 has the higher limits on both counts. Whisker rates it for up to five cats from 3 to 30 lb, with a 15.75 × 15.75 in entry and 17.5 in of interior height. PETKIT recommends the Ultra for cats from 3.3 to 22 lb. It publishes no cats-per-unit figure, though the Ultra’s camera recognizes cats by face, which helps in a multi-cat home.

The Ultra’s entry is the open question. We couldn’t confirm its size from PETKIT, so our cat safety checker can check weight and age but can’t size the doorway. WIRED’s description of the interior as “kind of cramped” is the only clue we have, and it points the wrong way for a long or heavy cat.

If your cat is over about 15 lb, treat the Ultra as unproven for your cat until you can see the entry measurement. Our large-cat guide and multi-cat guide cover the alternatives.

Safety: two open questions

This section matters more than any feature on the spec sheet. For the background, read are self-cleaning litter boxes safe?.

Litter-Robot 5. Whisker’s SafeCat system with OmniSense uses multiple lasers, weight sensors and anti-obstruction detection to spot a cat and stop the cycle. That is more layers than the Ultra lists. What we can’t confirm is whether the entry stays open for the whole cycle. Neither Whisker’s page nor a named review in our sources says so, and the LR5 isn’t one of the boxes WIRED confirms stay open. We’d expect it to behave like the Litter-Robot 4, which is one of those picks, but we won’t state that as fact.

Purobot Ultra. PETKIT and WIRED describe weight and proximity sensors working alongside the camera. Open entry during the cycle isn’t confirmed for the Ultra either.

Because both are unconfirmed, the practical advice is the same: weigh your cat, stay within the minimums, keep a regular box out during the switch, and watch the first cycles. Use our transition guide to do it gradually.

Kittens and small cats

• Litter-Robot 5: Whisker says a kitten under 3 lb should use it powered off, with cycles started by hand, until it reaches 3 lb.
• Purobot Ultra: PETKIT recommends it for cats at least 6 months old and at least 3.3 lb, per the Amazon listing.

What the Ultra does that the LR5 doesn’t

Auto-bagging

This is the Ultra’s main selling point. When the bag is full, the box seals it and loads a new one, so emptying is lifting out a sealed bag. The Litter-Robot 5 has a sealed, lined drawer but no auto-bagging, so you lift out and tie off the liner yourself. WIRED found the Ultra kept smells at bay.

The camera

The Ultra films visits with night vision and two-way audio, takes stool snapshots after each cycle and recognizes multiple cats by face. WIRED found the video black-and-white and low detail and the analytics flat. It’s fun to check, but we wouldn’t buy it for health monitoring.

The Litter-Robot 5 has no camera. If you want one in the Whisker range, the LR5 Pro costs $999 and has dual AI cameras, and WIRED says its AI needs Whisker+ to work reliably. That is a $200 jump over the LR5 before any subscription.

What the LR5 does that the Ultra doesn’t

WasteID

WasteID times cycles differently for urine and stool and logs which is which. In WIRED’s testing it, and weight-based cat identification, worked only intermittently for the first four months, then improved markedly after firmware updates. Both need Whisker+, about $80 a year per WIRED. Without the subscription you still have a capable cleaning robot.

Size and refilling

The Ultra is 46 lb and about 33 in tall, far heavier than the LR5’s 28.7 lb. WIRED also found the Ultra hard to refill with litter because the camera arm gets in the way. The LR5 is 29.9 in tall on a 22 × 27 in footprint, so measure your space either way. WIRED’s tester found the LR5’s touchscreen finicky and preferred the LR4’s physical buttons.

Litter and emptying

Both take clumping litter. Whisker recommends clumping clay for the LR5, and PETKIT sells tofu and mixed litters for the Ultra, which gives a little more choice. In WIRED’s testing the LR5 held about 10 days of waste from two cats. See our litter guide for specific picks.

Running costs

These are our default assumptions, not measured figures: about 10 lb of clumping litter per cat per month at Dr. Elsey’s Chewy price ($0.57 a pound), plus each maker’s consumables. The LR5 uses Whisker’s liners ($25 for 25) and one $5 carbon filter per cat per month. The Ultra uses PETKIT’s own bag rings and an odor eliminator at $20 for three refills (WIRED). We couldn’t confirm PETKIT’s bag-ring price, so we use Whisker’s $1-per-liner price as a stand-in.

Two things stand out. The Ultra costs less to run with two cats because the LR5’s per-cat liners and filters add up, and the LR5 costs more once Whisker+ is on. The Amazon bundle includes six months of Whisker+, which trims that. Enter your own prices in the cost calculator.

Buying guide: how to choose

1. Weigh your cat first. Over 22 lb rules out the Ultra by PETKIT’s own rating. Over 25 lb leaves the LR5 as the only hooded box we cover with a rating that high.
2. Count the cats. Three or more points to Whisker’s published ratings (up to five on the LR5). Use the box calculator to see how many boxes you need, because a robot doesn’t replace the n+1 rule.
3. Decide whether you want a camera. If yes and your budget is about $800, the Ultra is the one with a camera. If you want a camera for less, see the Max Pro 2 below.
4. Think about emptying. If handling a waste bag is what you dread, auto-bagging is the Ultra’s real advantage.
5. Check for a subscription. The LR5’s best features need Whisker+. The Ultra’s listing doesn’t mention one.
6. Measure the space. The Ultra is 46 lb and about 33 in tall. Place either box where you won’t need to move it.

Not sure? The litter box matcher narrows the list from your cats and budget.

Who should skip both

At about $800 each, these are the most expensive boxes we cover, and neither is the value pick.

• One or two cats under 19 lb: the Litter-Robot EVO costs about $599 and does the core job in less space.
• Up to four cats or a cat up to 25 lb: the Litter-Robot 4 costs about $699–749 and matches the LR5’s entry. See Litter-Robot 5 vs 4 vs EVO.
• You want a camera but not an $800 price: the Purobot Max Pro 2 is WIRED’s current favorite, with a 10.51 × 10.74 in entry (43% larger than the previous PETKIT generation) and a 1080p camera for about $500–550. It doesn’t bag its own waste.
• You’d rather pay half as much: the PuraMax 2 and others are in our Litter-Robot alternatives guide.

Buying now, with Black Friday around the corner

Retailers have begun early sales. We can’t promise a discount on either box, and prices move week to week. Compare the maker’s store with Amazon, and read our Black Friday deals guide before paying full price. Whisker’s Amazon listing is a bundle that includes a three-year warranty, so compare it with the $799 robot-only price rather than assuming the cheaper number is the better deal.

Useful extras: Dr. Elsey’s Ultra clumping clay, Whisker drawer liners for the LR5, and a Gorilla Grip 35 × 23 in mat in front of either box. For the Ultra, buy PETKIT’s own bag rings and odor refills, because its standard bag rolls and N50 refill don’t fit it.

Verdict

Buy the Litter-Robot 5 if you have a big cat, several cats, or want a box with the highest published limits and Whisker’s laser-and-weight sensing. Accept a subscription for WasteID, a touchscreen WIRED found finicky and a bundle-only Amazon listing. Check the Litter-Robot 5 price.

Buy the PETKIT Purobot Ultra if self-bagging and a camera on every visit are what you want, your cat is average-size, and you have room for a 46 lb box. Expect proprietary refills and an awkward refill because of the camera arm. Check the Purobot Ultra price.

If neither feature is a must-have, save $100–300 on the Litter-Robot 4, EVO or Purobot Max Pro 2. Once you’re set up, our troubleshooting guide covers ghost-cat errors and drawer-full alerts for both.