# Whisker Litter-Robot 4 vs Whisker Litter-Robot EVO

As of Oct 26, 2026, the Whisker Litter-Robot 4 costs $699 and the Whisker Litter-Robot EVO costs $599, so the Whisker Litter-Robot EVO is $100 cheaper. Pick the Whisker Litter-Robot 4 for one to four average size cats. Pick the Whisker Litter-Robot EVO for one or two average size cats in a small space.

Prices checked Oct 26, 2026. HTML version: https://robotsforthat.com/vs/whisker-litter-robot-4-vs-whisker-litter-robot-evo/

## Side by side

| | Whisker Litter-Robot 4 | Whisker Litter-Robot EVO |
|---|---|---|
| Price | $699 | $599 |
| 3 year cost | $1,035 | $599 |
| Our score | Not scored yet | Not scored yet |
| Rank in Litter box | #16 | #15 |
| Status | on sale | on sale |
| Warranty | 1 year (WhiskerCare), extendable to 3 years; 90 day in home trial | 1 year, 3 years with WhiskerCare ($99); 90 day in home trial |
| Cat weight range | 3 to 25 lb (kittens under 3 lb need semi automatic mode) | 3 to 19 lb |
| Max cats | Up to 4 | Up to 2 cats (maker) |
| Waste drawer | Sealed drawer with carbon filter, as little as once every 8 days (maker claim) | Sealed, carbon filtered drawer, up to 7 days for one cat (maker) |
| Sensors | Laser and weight sensors, SmartScale cat weight tracking, SafeCat system | Weight sensors and SafeCat anti obstruction system; no entry motion sensors (Vetstreet) |
| App | Whisker app (2.4 GHz WiFi); free 7 day view, Whisker+ optional | Whisker app (iOS and Android), 2.4 GHz WiFi only; Whisker+ membership optional |
| Litter type | Clumping clay recommended; crystals only if they pass the screen; plant based and pellet litters not recommended | Clay based clumping litter; crystal, plant, paper and pellet litters not recommended |
| Size | 22 x 27 in footprint, 29.5 in tall, 15.75 x 15.75 in entry, 24 lb empty | 20.6 x 24.3 in footprint, 27.6 in tall, 14.85 in entry, 21.5 lb empty |
| Noise | No dB rating published; QuietSift motor | Marketed as nearly silent (QuietSift); no dB figure given |
| Best for | one to four average size cats | one or two average size cats in a small space |
| Skip if | your cat is over 25 lb | you have a cat over 19 lb or three or more cats |

## What reviewers found

### Whisker Litter-Robot 4

- Cats.com: Runner Up in the October 2026 roundup; reliable and well built, but the smaller litter bed may not suit large cats. [Source](https://cats.com/reviews/best-self-cleaning-litter-box)
- The Irish Times: Quiet, no smells and a clean tray in a home test; sensors stopped the drum when a cat entered; app cat ID was less accurate for cats of similar size. [Source](https://www.irishtimes.com/technology/consumer-tech/review/2026/10/03/litter-robot-4-review-fed-up-with-scooping-cat-litter-try-this/)
- CNN Underscored: Drawer needed emptying about once a week with two cats; quieter than the Litter-Robot 3; cats took about a week to adjust. [Source](https://amp.cnn.com/cnn/cnn-underscored/reviews/litter-robot-4-review)

### Whisker Litter-Robot EVO

- Vetstreet: A veterinarian used it for about two weeks in a multi cat home and praised odor control and automation, but said the Litter-Robot 5 Pro would have suited her household better. [Source](https://www.vetstreet.com/pet-product-reviews/litter-robot)
- TechnoMEOW: Used for a couple of months with three or more cats; setup was quick, but a mat edge caused a position fault error and app disconnects were more frequent than on the Litter-Robot 4 until a firmware update. [Source](https://technomeow.com/litter-robot-evo-review/)

## Questions buyers ask

### Which is better, the Whisker Litter-Robot 4 or the Whisker Litter-Robot EVO?

Pick the Whisker Litter-Robot 4 for one to four average size cats. Pick the Whisker Litter-Robot EVO for one or two average size cats in a small space.

### Which is cheaper?

The Whisker Litter-Robot EVO at $599, versus $699 for the Whisker Litter-Robot 4, checked Oct 26, 2026. Over 3 years with running costs: $1,035 vs $599.

### What is the difference between the Litter-Robot 4 and the Litter-Robot EVO?

Cat weight range: 3 to 25 lb (kittens under 3 lb need semi automatic mode) on the Litter-Robot 4, 3 to 19 lb on the Litter-Robot EVO. Max cats: Up to 4 on the Litter-Robot 4, Up to 2 cats (maker) on the Litter-Robot EVO. Waste drawer: Sealed drawer with carbon filter, as little as once every 8 days (maker claim) on the Litter-Robot 4, Sealed, carbon filtered drawer, up to 7 days for one cat (maker) on the Litter-Robot EVO.

Full reviews: [Whisker Litter-Robot 4](https://robotsforthat.com/robot/whisker-litter-robot-4/index.md), [Whisker Litter-Robot EVO](https://robotsforthat.com/robot/whisker-litter-robot-evo/index.md)