After six months of daily use with two cats, the Litter-Robot 4 has earned its place as our #1 pick for best automatic self-cleaning cat litter box. It's not cheap at $699 — but it delivers on every promise with whisper-quiet operation, excellent odor control, and a genuinely useful smart app.
What Is the Litter-Robot 4?
The Litter-Robot 4 is the fourth generation of Whisker's flagship automatic self-cleaning litter box. It uses a rotating globe mechanism to sift clumping litter, depositing waste into a sealed carbon-filtered drawer below. The entire process takes about 2 minutes and happens automatically after your cat exits.
Key upgrades from the Litter-Robot 3 include a quieter motor, redesigned interior with OmniSense™ detection, a wider entryway, a more compact footprint, and a significantly upgraded app experience with weight tracking and usage patterns.
Performance Testing
We tested the Litter-Robot 4 across five key categories. Here's how it performed:
Pros and Cons
What We Love
- Nearly silent operation — won't wake you up at night
- Excellent odor control with sealed drawer + carbon filter
- Smart app tracks weight & usage per cat
- Extra-large waste drawer lasts 1–2 weeks (2 cats)
- Wider entry fits even large cats (up to 25 lbs)
- OmniSense™ prevents cycling when cat is inside
- 90-day money back guarantee
What Could Be Better
- $699 price is steep (but 90-day trial helps)
- Large footprint — needs about 25" × 25" of space
- Only works with clumping clay litter
- Initial cat adjustment period (1–2 weeks)
- Occasional pinch-detect false alarms with lightweight cats
Odor Control Deep Dive
Odor control is where the Litter-Robot 4 truly shines. The combination of rapid waste removal (within 7 minutes of use), a tightly sealed waste drawer, and activated carbon filter means we could place this in our bedroom without noticing any smell. In our testing, we found it outperformed every other model except the PetSnowy SNOW+ (which has a dedicated air purification system).
For multi-cat households, the fast cleaning cycle is critical — the box cleans itself long before the next cat needs to use it, maintaining a pristine litter bed at all times. This actually reduces litter usage by 30–50% compared to manual scooping, since waste is quickly removed before it can contaminate surrounding litter.
Smart App Experience
The Whisker app (free, no subscription) is one of the better smart pet apps we've tested. Key features include:
- Usage tracking: See when each cat uses the box and how often
- Weight monitoring: Track weight trends — invaluable for spotting health issues early
- Waste drawer level: Notification when it's time to empty
- Custom sleep mode: Pause overnight cycling for bedrooms
- Multi-unit support: Connect multiple Litter-Robots to one app
Who Should Buy the Litter-Robot 4?
The Litter-Robot 4 is ideal for:
- Multi-cat households — handles up to 4 cats effortlessly
- Busy professionals who want zero-maintenance litter
- Cat health-conscious owners who want weight and usage tracking
- Anyone tired of scooping who wants the best available option
It may NOT be ideal if you're on a tight budget (check the CATLINK Scooper Young instead) or have very limited space.
Our Verdict
Editor's Choice Award
The Litter-Robot 4 is the best automatic cat litter box we've tested. Period. It combines best-in-class cleaning performance, excellent odor control, and genuinely useful smart features into a product that reliably works day after day. The $699 price tag is significant, but the 90-day in-home trial makes it a risk-free purchase. If you can afford it, buy it.
Check Price on Amazon