Introducing SmartScale®

Using an advanced algorithm, SmartScale® identifies trends in your cats’ weight all within the Whisker app.

Know more about your cat's health

Individual cat recognition

Weight sensor technology detects the weight of individual cats (who weigh a difference of 1 or more lbs).*

Pet weight

Charts your cat’s weight over time, so you can keep tabs on their health.

Wellness insights

Monitor individual pet activity and trends to identify patterns and irregularities.

How SmartScale® works

Algorithm icon

SmartScale uses an advanced algorithm to determine which cat is using Litter-Robot 4.

Analyze Logo

SmartScale analyzes individual weight data and automatically displays it in your Pet Profile.

Daily Tracking Logo

See when each cat used the Litter-Robot 4 and track their daily weight over time.

Weightscale animation

Over 70 million weight data points

Every month, our cluster algorithm is finely tuned to classify individual weight readings from Litter-Robot 4 users and assign them to each of your Pet Profiles.

SmartScale® app on phone

SmartScale® is easy to use

  1. Download the Whisker app and connect your Litter-Robot 4.
  2. Open the Whisker app and create a Pet Profile for each of your pets.
  3. After your cat uses Litter-Robot, you can view individual weight trends charts in Pet Profile.


  • Is it free?

    Yes! SmartScale® is available for every Litter-Robot 4 user. Simply download the Whisker App and complete your Pet Profiles to activate SmartScale®.
  • How does the algorithm work?

    The SmartScale® algorithm functions by gathering cat weight data over a 7-day period. Once there is enough history of data for your cat, subsequent readings will be assigned to that cat. SmartScale® uses a KDE (Kernel Density Estimation) maxima algorithm to locate the most probable average values in a dataset by creating a smooth curve that fits the weight readings. It's like a high-tech version of "connect the dots" that allows us to define clusters of cat weight readings that belong to the same cat. SmartScale® evaluates new pet weight readings from LR4 using this algorithm to determine if a cat's weight has changed.
  • If I have two cats that weigh similar amounts, can you distinguish them?

    The SmartScale® system distinguishes between multiple cats by tracking their weight. If your cats are within 1 pound of each other, we will unfortunately not be able to distinguish between them. In this case, the SmartScale® feature will automatically turn off.
  • Is there any additional hardware required?

    In most cases, no additional hardware is necessary. However, if your Litter-Robot 4 is placed on medium to high pile carpet, you’ll need to either move the robot to a hard floor (like tile or hardwood) or purchase our carpet tray accessory. This will ensure consistent and precise weight readings.
  • *What’s the lowest weight supported by SmartScale®?

    The Litter-Robot 4 and our SmartScale® feature require cats that weigh 3 lbs or greater.
  • Do I have to use Pet Profile to use SmartScale®?

    Yes. SmartScale® requires a dedicated Pet Profile for each pet. A completed profile with accurate weight input plays a crucial role in properly recording and assigning weight data to each pet.
  • Can I see a chart with all my cats' weights instead of one per cat?

    At this time, you cannot. However, we are working on new features and charts to help customers better understand their pets habits. We look forward to introducing our continued product releases.
  • What are the reasons SmartScale® could be not be working for me?

    1. You do not own a Litter-Robot 4.
    2. Your Firmware is not updated. Your robot needs to be running firmware 2.85 or newer for SmartScale®  to be enabled.
    3. Your Litter-Robot may be on a soft surface (such as carpet) and is unable to accurately weigh your cat. To resolve this, either move the robot to a hard floor (like tile or hardwood) or purchase our carpet tray accessory. 
    4. The weight in your pet's profile may not be accurate. If it is off by more than one pound, SmartScale® readings will not register properly. To resolve this, check the weight readings in your Robot's History and update your pet's profile accordingly.
    5. Two or more cats may share an almost identical weight. Unfortunately, there is no way for us to distinguish between cats that weigh within one pound of each other.
    6. Your Litter-Robot is pushed up against a wall. To correct this, slide the robot away from the wall so it isn’t touching it.
  • How do I update my firmware?

    How to update to version 2.85

    Step 1: Select your Litter-Robot 4 from the app's main dashboard. 

    Step 2: Tap on the Settings icon located in the top right corner.  

    Step 3: Check for available updates by looking for an orange dot on the Firmware Information row. If you see it, tap on it.  

    Step 4: Select "Update Firmware."  

    Step 5: After the update, tap "Okay" to return to the main app.

  • What happens if there are other cats in the home without pet profiles using the Litter-Robot 4?

    When other cats without a pet profile use the Litter-Robot 4, weight readings will be seen as unhealthy data. When too many data points are classified as unhealthy, SmartScale will be turned off. If you are an individual or organization that fosters or rescues cats, you’ll need to set up a Pet Profile for each cat in order for SmartScale to function and filter data properly.