Litter & Litter Tech
Litter-Robot 4 vs Litter-Robot 5
Whisker publishes surprisingly little about either. What it does publish makes the choice simple, and it comes down to one number.
Affiliate disclosure: we earn a commission if you buy through our links, at no extra cost to you. It never changes which product we rank first — here is how we're funded.
Everyone in this category says they tested twenty litter boxes. We have not tested any, and we say so. What we do instead: compile the published specs, read the manuals, and do the arithmetic on what this gear costs to run and how it behaves once there is more than one cat using it. Every spec is linked to the document it came from. Prices are checked daily — last verified January 1, 1970. Here is exactly how we pick.
The Litter-Robot 4 is $699 and the Litter-Robot 5 is $799. Whisker publishes enough about the difference to make the decision, but not nearly as much as you would expect for a thousand-dollar-class purchase — and what it withholds is as revealing as what it states.
Side by side, from Whisker’s own pages
| Specification | Litter-Robot 4 | Litter-Robot 5 |
|---|---|---|
| Price from | $699 | $799 |
| Cats supported | Not published | Up to 5 |
| Cat weight range | 3-25 lb | 3-30 lb |
| Entryway | 15.75" x 15.75" | 15.75" x 15.75" |
| Footprint | 22" W x 27" D | 22" x 27" |
| Height | 29.5" | 29.9" |
| Weight, empty | 24 lb | 28.7 lb |
| Globe capacity | Not published | Not published ("slightly larger") |
| Waste drawer capacity | Not published | Not published ("improved... and size") |
| Display | Not specified | LCD |
| Waste recognition | No | WasteID |
| Warranty | 1 year, 3-year plan optional | 1 year, 3-year plan $100 |
Every row is quoted or summarized from Whisker's own Litter-Robot 4 and Litter-Robot 5 product pages, read 3 September 2026. Rows marked 'not published' are blank on Whisker's site; we have not estimated them.
The one number that decides it
This matters more than it sounds. In a category where nobody publishes drawer volume, a manufacturer that will commit to a specific number of cats is giving you the only capacity signal available. It is a claim Whisker can be held to. “Slightly larger globe” is not.
Where each one wins
The 4 wins on price, and only on price
It is $100 cheaper, 4.7 lb lighter to move when you clean under it, and half an inch shorter. The entryway is identical, the footprint is identical, and for a one- or two-cat household with cats under 25 lb there is nothing the 5 does that changes your week.
The 5 wins on headroom
A published five-cat rating, a weight range extended to 30 lb, a bigger drawer and waste recognition. If you have a large breed — a Maine Coon, a Ragdoll, a big Norwegian Forest cat — the 25 lb ceiling on the 4 is a genuine constraint and the 5 is the only one of the two you should be considering.
The verdict by household
| Household | Buy | Why |
|---|---|---|
| 1 cat, average size | Neither, probably | Two ordinary boxes cost a fraction and satisfy the Cornell n+1 count. See our worth-it guide. |
| 2 cats, average size | Litter-Robot 4 | Nothing the 5 adds applies. Save the $100 toward the consumables. |
| 3 cats | Litter-Robot 5 | Published headroom is worth paying for at the point where capacity starts to bind. |
| 4-5 cats | Litter-Robot 5 | The only unit here with a published rating that covers you. |
| Any cat over 25 lb | Litter-Robot 5 | The 4's published weight range stops at 25 lb. |
The cost neither page quotes
Both units share the same consumable model, and with three cats it runs to roughly $228 a year at Whisker’s own listed prices — $156 of drawer liners and $72 of carbon filters, worked out in full on the running-costs page. That is a third of the purchase price again, every year, and it is identical whichever of the two you buy. Factor it in before the $100 difference feels significant.
The comparison neither of these wins
If you are choosing between the 4 and the 5 with an open mind, it is worth knowing that the Neakasa M1 publishes both its litter capacity (7.17 L) and its waste capacity (11.23 L), takes ordinary bin bags rather than proprietary liners, and states a noise figure. On published data it is a more transparent product than either Litter-Robot, which is why it leads our automatic box roundup. What it does not do is contain odor the way an enclosed drawer does — it is open-topped by design.
The gear discussed here
Specs are the manufacturer's own, linked to the page they came from. Prices come from a live daily check; where we have no verified price we say so rather than print a stale one.
Whisker Litter-Robot 5
Whisker · Automatic litter box · Our score 8.4/10
Reference link This one sells direct and we earn nothing on it. We link it anyway because it belongs in the comparison. How we're funded.
The only enclosed automatic box here that carries a published cat-count rating, and the rating is five -- which is the whole reason to pay the extra $100 over the 4.
Published specs
| Cats supported | Up to 5 (published) |
|---|---|
| Cat weight range | 3-30 lb |
| Entryway | 15.75" x 15.75" |
| Footprint / height | 22" x 27", 29.9" H |
| Weight, empty | 28.7 lb |
| Warranty | 1 year WhiskerCare, 3-year plan $100 |
| Drawer capacity | Not published; described only as larger than LR4 |
Source: Whisker -- Litter-Robot 5 product page
$799 list divided by the five cats Whisker rates it for. The Litter-Robot 4 at $699 carries no published cat rating, so the same sum cannot be done for it -- which is itself the argument for the 5 in a big household.
What the specs favor
- Published rating for up to five cats -- the only unit here that states one
- Cat weight range extended to 30 lb, up from 25 lb on the LR4
- Same 15.75-inch square entryway as the LR4
- Larger waste drawer than the LR4, per Whisker
What they don't
- $100 more than the LR4 for a household that does not need the extra rating
- Whisker still does not publish a drawer volume in liters or gallons
- 4.7 lb heavier than the LR4, which matters if you move it to clean
- Direct-sale, so no reliable Amazon price history
You have one or two cats. Everything the 5 adds over the 4 -- bigger drawer, higher weight ceiling, five-cat rating -- is headroom a two-cat house will never reach.
How it scores
Scores are our editorial weighting of the published specs above, not a test result. They are deliberately kept out of this page's structured data.
Whisker Litter-Robot 4
Whisker · Automatic litter box · Our score 8.1/10
Reference link This one sells direct and we earn nothing on it. We link it anyway because it belongs in the comparison. How we're funded.
The biggest entryway and the largest published cat-weight range of the enclosed units, and the only one whose maker publishes an actual power-supply spec you can cost out.
Published specs
| Entryway | 15.75" x 15.75" |
|---|---|
| Footprint / height | 22" W x 27" D x 29.5" H |
| Weight, empty | 24 lb |
| Cat weight range | 3-25 lb |
| Power supply | 15 V DC, 400-1000 mA (6-15 W) |
| Warranty | 1 year, 3-year plan optional |
| Globe / drawer capacity | Not published by Whisker |
Source: Whisker -- Litter-Robot 4 product page and power supply spec article
Whisker's own spec sheet accepts a 15 V supply between 0.4 A and 1.0 A. Take the 1.0 A ceiling: 15 W x 24 h x 365 = 131.4 kWh, x $0.1834 = $24.10. That assumes the motor runs flat out every hour of the year, which it does not -- so the real figure is well below this. The consumables are the actual cost.
What the specs favor
- Largest published entryway of the enclosed units here, at 15.75 inches square
- Whisker publishes a real power-supply rating, so running cost is computable
- Cat weight range published as 3-25 lb
- Three-year extended warranty available at purchase
What they don't
- Whisker does not publish globe or waste-drawer capacity, which is the number that actually decides how often you empty it with three cats
- Waste drawer liners are a proprietary consumable at $25 per 25-pack
- Carbon filter is a separate monthly consumable
- Sells mainly direct, so there is no reliable Amazon price to track
You have five cats. Whisker rates the newer Litter-Robot 5 for up to five and this one carries no published cat-count rating at all -- buying the older unit for a bigger household is guessing.
How it scores
Scores are our editorial weighting of the published specs above, not a test result. They are deliberately kept out of this page's structured data.
Common questions
Is the Litter-Robot 5 worth the extra $100 over the 4?
What is actually different between the Litter-Robot 4 and 5?
How big is the Litter-Robot waste drawer?
Do the Litter-Robot 4 and 5 use the same accessories?
How much electricity does a Litter-Robot use?
Sources
Read next
- Best Automatic Litter Boxes for Multiple Cats (2026)
Five automatic boxes ranked on published litter and waste capacity, and on what a year of consumables actually costs with three cats.
- What an Automatic Litter Box Actually Costs to Run
The full year-one and year-two running cost of every major automatic litter box, computed from published prices with the arithmetic shown.
- Are Automatic Litter Boxes Worth It?
Break-even arithmetic against ordinary boxes, worked from published prices, with a clear answer for one, two and three cat households.
- How Many Litter Boxes Per Cat?
The n+1 rule, its published source, a count-by-household table, and why four boxes in a row is really only one box.
- Litter Setup for Multiple Cats
Box counts, room-by-room placement, which box types to mix and why, for households with two or more cats.