Whisker Litter-Robot 4 vs Whisker Litter-Robot 5

Both makers say their sensor detects cats from 3 lb, so the kitten threshold does not separate them. For a large cat, the Whisker Litter-Robot 5 is rated to 30 lb and the Whisker Litter-Robot 4 to 25. Every other published figure for both is in the table, with the rows where they differ tinted.

Whisker Litter-Robot 4 self-cleaning litter box

Whisker

Whisker Litter-Robot 4

Automate from ~3 lb / ~3 monthsAnti-pinch protection

~$699

Four years on, this is still the reference point everything else in the category gets measured against.

Best for: Two or three average cats in a home that already uses clay clumping litter

Days between emptying

The maker publishes no drawer volume, so the days cannot be worked out. Its own claim is up to 8 days for one cat.

Whisker Litter-Robot 5 self-cleaning litter box

Whisker

Whisker Litter-Robot 5

Automate from ~3 lb / ~3 months

~$799

Whisker's 2025 replacement for the LR4 keeps the same 22-by-27-inch footprint and entry but raises the rated weight to 30 lb and the cat count to five.

Best for: Large multi-cat homes that want visit-level tracking without a camera

Days between emptying

The maker publishes no drawer volume, so the days cannot be worked out. Its own claim is up to 10 days for one cat.

Specification comparison of the Whisker Litter-Robot 4 and the Whisker Litter-Robot 5
SpecificationWhisker Litter-Robot 4Whisker Litter-Robot 5
Approx. price~$699~$799
TypeRotating drumRotating drum
Kitten gateAutomate from ~3 lb / ~3 monthsAutomate from ~3 lb / ~3 months
Min. detection weight3 lb3 lb
Max. cat weight25 lb30 lb
Big-cat fitRated for large breeds (to 25 lb)Rated for large breeds (to 30 lb)
Entry opening15.75 × 15.75 in15.75 × 15.75 in
Entry step6.9 in off the floor7 in off the floor
Interior height16.5 in17.5 in
Footprint22 × 27 in × 29.5 in tall22 × 27 in × 29.9 in tall
Maker's drawer claimUp to 8 days, one catUp to 10 days, one cat
Cats supportedUp to 4Up to 5
Litter systemClumping litterClumping litter
Litters listedclumping clayclumping clay, silica crystal
Litters to avoidtofu, clumping wood/pine, non-clumping, paper, pellets, silica crystaltofu, clumping wood/pine, non-clumping, paper, pellets
Weight sensorYesYes
Anti-pinch protectionStated by the makerNot stated by the maker
Infrared / radarYesYes
CameraNoNo
Wi-Fi appYesYes
Running costNo required consumableNo required consumable
Bags / linersStandard trash bag or Whisker's custom-fit drawer linersWhisker custom-fit drawer liners ($25 for 25)
Warranty1 year1 year
First listed20222025

Whisker Litter-Robot 4: what it gives up

  • Whisker publishes no drawer volume, only an 'about every 8 days for one cat' estimate
  • Needs 2.4 GHz Wi-Fi; 5 GHz networks are not supported
  • Plant-based, pine, pellet and white crystal litters are all on the do-not-use list
  • At 22 by 27 inches it wants a floor spot bigger than most ordinary boxes

Whisker Litter-Robot 5: what it gives up

  • No published drawer volume, so the ten-day claim cannot be checked against arithmetic
  • Whisker does not describe pinch detection on this model the way it does for the LR4
  • 2.4 GHz Wi-Fi only
  • Some app insights sit behind the Whisker+ membership

Full pages: Whisker Litter-Robot 4 · Whisker Litter-Robot 5