Which Litter-Robot should you buy?
For one or two cats up to 19 lb, buy the Litter-Robot EVO; for 3 to 4 cats or a cat over 19 lb (up to 25 lb), the Litter-Robot 4. Each is the cheapest Litter-Robot that Whisker rates for those cats. Count your cats and weigh the heaviest one, then find your row below. Tap a name for its full limits.
$599One or two cats, up to 19 lb
Litter-Robot EVO
up to 2 cats · 3–19 lb
$699- $799
5 cats, or a cat over 25 lb (up to 30 lb)
Litter-Robot 5
up to 5 cats · 3–30 lb
Whisker only - $899
You want a camera to tell cats apart
Litter-Robot 5 Pro
Same as the 5, plus cameras
Whisker only
Whisker sells four Litter-Robots: the EVO for up to 2 cats of 3-19 lb, the 4 for up to 4 cats of 3-25 lb, and the 5 and 5 Pro for up to 5 cats of 3-30 lb. On November 2, 2026, Amazon sold the EVO ($599) and the 4 ($699) new; we found no new Amazon listing for the 5 or 5 Pro. We compare Whisker’s figures; we do not test Litter-Robots.
Want a cheaper box? Litter-Robot alternatives picks self-cleaning boxes from other brands that cost less.
Find your cats on one chart
Prices: EVO $599 · 4 $699 · 5 $799 · 5 Pro $899 (Amazon for the EVO and 4; Whisker for the 5 and 5 Pro).
Whisker's numbers are the most it rates each box for. A house right at a limit, such as two cats in the EVO, is rated by Whisker, but every extra cat fills the drawer sooner than the one-cat figure. The same rule picks on Litter-Robot 5 vs 4, the Litter-Robot 4 page and the best automatic litter box.
The four Litter-Robots, side by side
| Model | Cats | Cat weight | Empty every | Price |
|---|---|---|---|---|
| EVO | 2 | 3–19 lb | 7 days | $599 |
| 4 | 4 | 3–25 lb | 8 days | $699 |
| 5 | 5 | 3–30 lb | 10 days | $799 Whisker only |
| 5 Pro | 5 | 3–30 lb | 10 days | $899 Whisker only |
Whisker’s figures. “Empty every” is for one cat; more cats fill the drawer sooner. Prices: Amazon on November 2, 2026 for the EVO and 4; Whisker’s own price for the 5 and 5 Pro.
Size and features for all four
| Feature | EVO | 4 | 5 | 5 Pro |
|---|---|---|---|---|
| Opening | 14.85 in | 15.75 in | 15.75 in | 15.75 in |
| Inside height | 14.5 in | 16.5 in | 17.5 in | 17.5 in |
| Height | 27.6 in | 29.5 in | 29.9 in | 29.9 in |
| Floor space | 20.6 × 24.3 in | 22 × 27 in | 22 × 27 in | 22 × 27 in |
| Weight, empty | 21.5 lb | 24 lb | 28.7 lb | 29.6 lb |
| Screen | color screen | status lights | color screen | color screen |
| On carpet | any floor | add a Carpet Tray | any floor | any floor |
| Camera | — | — | — | 2 cameras |
| Tells pee from poop | — | — | yes | yes |
| LitterHopper | — | 13 cups | 17.3 cups | 17.3 cups |
| WiFi | 2.4 GHz only | 2.4 GHz only | 2.4 GHz only | 2.4 or 5 GHz |
From Whisker’s comparison chart and model pages: carpet, pee and poop, LitterHopper, WiFi, screen.
What each costs to own for 3 years
Whisker says to change the OdorTrap pack every 2–4 weeks on every model (Whisker). The same packs fit any Litter-Robot (Whisker). At Whisker’s store price, $30 for 6, that is $65–$130 a year. We read Whisker’s price on November 2, 2026 (Whisker).
| Model | Price | OdorTrap, 3 years | Total, 3 years |
|---|---|---|---|
| EVO | $599 Amazon | $196–$391 | $795–$990 |
| 4 | $699 Amazon | $196–$391 | $895–$1,090 |
| 5 | $799 Whisker | $196–$391 | $995–$1,190 |
| 5 Pro | $899 Whisker | $196–$391 | $1,095–$1,290 |
Not counted: litter, which every box needs, and carbon filters. Whisker’s filters fit the EVO, 4, 5 and 5 Pro (Whisker). Amazon does not sell them. At Whisker’s $30 for 6, they add about $65–$130 a year to any model.
Who each one is for
We do not test Litter-Robots. Each pick is the lowest-priced model Whisker rates for the house. Price decides only between models that are rated for it.
Litter-Robot EVO
For: One or two cats, up to 19 lb
The smallest and cheapest. Whisker made it for “1-cat homes, small cats, first-time cat parents, smaller spaces” (Whisker). It takes 20.6 × 24.3 in of floor. Its opening is 14.85 in and the inside is 14.5 in high. Whisker says that for an especially large or tall cat, get the 5 or 4 instead (Whisker).
Litter-Robot 4
For: 3 to 4 cats, or a cat over 19 lb (up to 25 lb)
The middle model. Whisker calls it “the tried and true Litter-Robot” (Whisker). It is rated for twice as many cats as the EVO and cats up to 25 lb. Unlike the EVO, it senses the litter level (Whisker). Its add-on LitterHopper refills litter for you: $129 from Whisker. Litter-Robot 4 size, refills and bundles.
Litter-Robot 5
For: 5 cats, or a cat over 25 lb (up to 30 lb)
The only model rated for a fifth cat or a cat over 25 lb. It is the same floor size as the 4 but 1 in taller inside. It tells pee from poop, which Whisker calls WasteID (Whisker). Drawer: up to 10 days with one cat. Whisker sells it on its own site; we found no new Amazon listing on November 2, 2026.
Litter-Robot 5 Pro
For: You want a camera to tell cats apart
The Litter-Robot 5 with two 1080p cameras (Whisker). Live view for 5 minutes a day and recorded clips are free (Whisker). Telling cats apart by face needs a Whisker+ plan (Whisker). The Pro now comes with the first year of it free (Whisker). It is the only model that works on 5 GHz WiFi (Whisker). Same limits as the 5. Whisker-only too.
See also: Neakasa M1 Plus vs Litter-Robot 4: which to buy.
See also: PETKIT PuraMax 2 vs Litter-Robot 4: which to buy.
Questions buyers ask
Which Litter-Robot should I buy?
One or two cats, up to 19 lb: the Litter-Robot EVO. 3 to 4 cats, or a cat over 19 lb (up to 25 lb): the Litter-Robot 4. 5 cats, or a cat over 25 lb (up to 30 lb): the Litter-Robot 5. You want a camera to tell cats apart: the Litter-Robot 5 Pro. Each is the lowest-priced model Whisker rates for that house.
Is the Litter-Robot 5 worth it over the 4?
Only if you need what the 4 is not rated for: a fifth cat or a cat over 25 lb. The 5 costs $100 more. Refills cost the same, so it is still about $100 more over 3 years. For that you get 10 days between emptying instead of 8, pee-or-poop tracking, a color screen and more room inside. It also works on carpet without a tray. If your cats fit the 4’s limits, the 4 does the same job for less. Every change from the 4 to the 5.
Litter-Robot 5 or 5 Pro?
The Pro adds two cameras and costs $100 more. The limits and size are the same. Without a plan you get 5 minutes of live view a day and recorded clips (Whisker). Telling cats apart by face needs Whisker+, at $7.99 a month or $79.90 a year (Whisker). The Pro comes with the first year free (Whisker). Get the Pro if two of your cats weigh about the same. Whisker says its scale may have trouble telling those cats apart (Whisker).
Litter-Robot EVO or 4?
Whisker calls the EVO “a more compact version of Litter-Robot 4” (Whisker). Get the EVO for one or two cats up to 19 lb in a small space. It costs $100 less. Get the 4 for a third or fourth cat, a cat over 19 lb, or the LitterHopper. The 4 is 2 in taller inside, and its opening is 0.9 in wider.
Litter-Robot 3 or 4?
The Litter-Robot 3 Connect is gone. Whisker says it “is no longer available” (Whisker). Owners keep their warranty, Whisker says (Whisker). Compared with the 4, its opening is narrower: 10.25 × 15.25 in against 15.75 in round (Whisker). A cat must weigh at least 5 lb to use it (Whisker), against 3 lb on every model now. Whisker now points Litter-Robot 3 shoppers to the EVO (Whisker).
Which Litter-Robot is the biggest, and best for large cats?
The 5 and 5 Pro. Whisker rates them for cats up to 30 lb, with 17.5 in of room inside. They take the same 22 × 27 in of floor as the 4 and stand 29.9 in tall. The 4 is rated to 25 lb. Large cats, every brand.
Which Litter-Robot has a camera?
Only the 5 Pro. It has two: one faces out to see which cat comes in, and one looks at the litter bed (Whisker). The other models tell cats apart by weight (Whisker).
Does the LitterHopper fit every Litter-Robot?
No. There are two. The Litter-Robot 4 LitterHopper fits only the 4 and holds 13 cups (Whisker). The Litter-Robot 5 LitterHopper fits only the 5 and 5 Pro and holds 17.3 cups (Whisker). Each costs $129 from Whisker. Neither fits the EVO.
Do I need Whisker+?
No. The free Whisker app shows 7 days of visits and each cat’s weight (Whisker). Whisker+ adds up to 2 years of history for $7.99 a month or $79.90 a year, with a 30-day free trial (Whisker). It works with all four models (Whisker). On the 5 Pro, it also turns on face matching.
Can I buy the Litter-Robot 5 on Amazon?
We found no new Amazon listing for the 5 or 5 Pro on November 2, 2026. Whisker sells both on its own site. Amazon sold the EVO and the 4 new. Whisker’s 90-day home trial is for robots bought from Whisker. If you buy on Amazon, returns go through Amazon’s seller (Whisker).
Can a Litter-Robot go on carpet?
Yes. Whisker says the EVO, 5 and 5 Pro work on any floor (EVO, 5, 5 Pro). The 4 works on carpet too. On carpet 3 mm or thicker, Whisker suggests its Carpet Tray so the cat scale reads right (Whisker).
How much does a Litter-Robot cost to own?
The EVO: about $795–$990 over 3 years. The 4: about $895–$1,090 over 3 years. The 5: about $995–$1,190 over 3 years. The 5 Pro: about $1,095–$1,290 over 3 years. That is the price plus OdorTrap packs every 2–4 weeks. Litter and carbon filters are extra.
Sources
Whisker’s pages read October 1, 2026; the OdorTrap price on November 2, 2026. Amazon prices and listings checked November 2, 2026. These are Whisker’s figures, not our tests. How we work.
All 11 sources
- Whisker: compare Litter-Robot models
- Whisker: Litter-Robot EVO page
- Whisker: Litter-Robot 4 page
- Whisker: Litter-Robot 5 page
- Whisker: Litter-Robot 5 Pro page
- Whisker: Litter-Robot 5 LitterHopper page
- Whisker: LitterHopper page
- Whisker: OdorTrap packs
- Whisker: carbon filters
- Whisker: Whisker+ page
- Whisker: Litter-Robot 3 Connect page (discontinued)
Next: Litter-Robot 5 vs 4 · Litter-Robot 4 · best automatic litter box, every brand · Litter-Robot alternatives · multiple cats · kittens
Whisker Litter-Robot EVOOur pick for one or two cats
$599 at Amazon