Litter-Robot 4 vs. 5 vs. 5 Pro: Which to Buy
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Quick answer: The Litter-Robot 4 ($699) is still the value pick for up to four cats of 25 lbs or less. The Litter-Robot 5 ($799) is the better buy for most new purchases: it handles up to five cats and 30 lbs, has a larger waste drawer, detects solid versus liquid waste (WasteID), and ships with a built-in carpet tray. The 5 Pro ($899) only makes sense if you want its built-in cameras, and its AI cat identification and unlimited live streaming need a Whisker+ membership (about $7.99/month), which brings a Pro to roughly $1,140-1,190 over three years.
Our self-cleaning litter box guide and Litter-Robot 4 vs. homerunPET CS106 comparison were written around the Litter-Robot 4, which is no longer the only current model. Whisker now sells three generations at three prices, and the right choice depends less on brand loyalty than on how many cats you have, how big they are, and whether you actually want cameras.
The three models side by side
| Litter-Robot 4 | Litter-Robot 5 | Litter-Robot 5 Pro | |
|---|---|---|---|
| List price | $699 | $799 | $899 |
| Cats / weight | Up to 4 cats, 3–25 lbs | Up to 5 cats, 3–30 lbs | Up to 5 cats, 3–30 lbs |
| Waste drawer (one cat) | Empty about every 8 days | About every 10 days | About every 10 days |
| WasteID (solid vs. liquid) | No | Yes | Yes |
| Cameras | No | No | Dual 1080p |
| Carpet tray | Sold separately | Built in | Built in |
| Whisker+ membership | Optional | Optional | Needed for AI cat ID and unlimited streaming |
Prices are Whisker’s list prices; retailers discount, and the 4 is often cheaper. Confirm current numbers before buying.
What the extra $100 buys from the 4 to the 5
The 5 raises the ceiling on both cats and weight, stretches the waste drawer, adds WasteID, which adjusts the cycle by waste type, and puts a full-color LCD on the box that shows visit and cycle information without opening the app. A hands-on April 2026 review also found it quieter and smoother than the 4, sturdier, less fussy about sitting on carpet, better at odor control, and with a bin that needs emptying about every seven to ten days.
The same review lists real drawbacks, which matter more than the spec sheet: the 5 doesn’t take the Litter-Hopper attachment the 4 supports, bin-full alerts sometimes fire when the bin is only half full, the sensors occasionally label urine as solid waste, the indented buttons sometimes need a second press, and settings can only be changed in the app. Reviewers who compare the two generally land in the same place: the 5 is the better choice for most people buying new, and the 4 stays the better value when it is meaningfully cheaper.
What the extra $100 buys from the 5 to the 5 Pro
The Pro is the 5 plus dual 1080p cameras, one inside the globe and one outside, which let you watch a livestream while you’re away and, with the membership, identify which cat used the box. The catch is that the membership does a lot of the work. AI visual cat identification requires Whisker+, live streaming is capped at 5 minutes a day without it, and saved footage is limited to two days by default.
At about $7.99/month or $79.90/year, subscribing for three years takes the Pro to roughly $1,140 (annual billing) to $1,190 (monthly billing), against $799 for a 5 with no subscription. That is a fair price if you want to see your cats and confirm which one is changing bathroom habits, and poor value if you just want a litter box that cleans itself. If per-cat health data is the real goal, compare it with a retrofit litter box monitor before paying for cameras.
Who should buy which
- Choose the Litter-Robot 4 if: you have up to four cats, none over about 25 lbs, you’re on hard flooring, and the price gap to the 5 is $100 or more.
- Choose the Litter-Robot 5 if: you have a larger cat or more than four cats, you have carpet, you want waste-type detection and a bigger drawer, or the price gap to the 4 is small. It’s the default pick for most new buyers.
- Choose the 5 Pro if: you specifically want live video and camera-based cat identification, and you’re comfortable paying the membership on top of the hardware. Our subscription cost guide shows how that recurring fee compares with other pet devices.
- Skip all three if: you have one small cat and a tight budget. Our self-cleaning litter box guide covers cheaper options, and the homerunPET CS106 comparison covers a roomier rival at the same price as the 4.
Verified 2026-10-10 against Whisker’s own model comparison, a hands-on April 2026 review of the 5 and 5 Pro, and a September 2026 buyer’s comparison of the 5 and 4. Whisker+ pricing comes from launch coverage ($7.99/month or $79.90/year); one reviewer rounds it to $8/month after a free trial. We haven’t tested these units ourselves; where sources disagree or were silent, such as the 5 Pro’s exact noise level, we’ve left the detail out rather than guess.
Bottom line
Buy the Litter-Robot 5 if you’re buying new and the price gap is small, since it is the best balance of capacity, convenience and cost. Buy the Litter-Robot 4 if it’s meaningfully cheaper and your cats fit its limits. Pay for the 5 Pro only if the cameras and AI cat identification are what you actually want, and budget for Whisker+ when you do.
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Frequently asked questions
Is the Litter-Robot 5 worth $100 more than the Litter-Robot 4?
For most new buyers, yes. Per Whisker's own comparison, the 5 raises the limit from 4 cats and 25 lbs to 5 cats and 30 lbs, stretches the waste drawer from roughly 8 days to roughly 10 days for a single cat, adds WasteID (solid versus liquid waste detection) and a full-color LCD, and includes the carpet tray that the 4 sells as an add-on. If your cats are under 25 lbs, you have four or fewer, and the 4 is on sale at a meaningful discount, the 4 remains the better value.
Do I need Whisker+ for the Litter-Robot 5 Pro?
Not to use the box — it cleans and runs from the app without it. But the features that justify buying the Pro lean on the membership: AI visual cat identification requires Whisker+, and live camera streaming is limited to 5 minutes a day without it (unlimited with it). Whisker+ is about $7.99/month or $79.90/year, so the Pro's real three-year cost if you subscribe throughout is roughly $1,140-1,190 rather than the $899 sticker price.
Which Litter-Robot is best for a big cat or several cats?
The 5 or 5 Pro. Both are rated for up to 5 cats and cats up to 30 lbs, versus 4 cats and 25 lbs for the Litter-Robot 4. One reviewer notes that cats over 30 lbs, including some Maine Coons, may still find the 5 cramped, so measure a very large cat before buying any of them.
Is the Litter-Robot 4 still worth buying now that the 5 exists?
Yes, if the price gap suits you. The 4 is the previous generation, still sold, and reviewers describe it as the best value in the lineup because it costs $100-200 less than the 5 and 5 Pro. It lacks WasteID and cameras, needs a carpet tray add-on on carpet, and has the smaller cat and weight limits. Check current availability and price before buying, since stock of a previous-generation model can change.