Best litter for the Litter-Robot 4
Buy Tidy Cats Designed for Litter-Robot. Whisker, the company that makes the Litter-Robot 4, names it one of its two best litters. It was $19.98 for 22 lb on Amazon on November 2, 2026. Want no scent and a lower price per pound? Get Dr. Elsey's Ultra Unscented, a clay litter Whisker says works: $22.99 for 40 lb. For the waste drawer, use white 13-gallon kitchen bags. Whisker says white bags work best, and $15.34 buys 90.
| For | What to buy | Per unit | Price |
|---|---|---|---|
| Our pick | Tidy Cats Designed for Litter-Robot, 22 lb Whisker names it a best litter for the Litter-Robot. Scented: the scent comes out when the box cycles. | $0.91 a lb | $19.98 at Amazon |
| No scent, lower cost | Dr. Elsey's Ultra Unscented, 40 lb Clay. Whisker says it works in the Litter-Robot. Unscented. | $0.57 a lb | $22.99 at Amazon |
| Whisker's own litter | Lit, 20 lb Whisker’s other best pick. Sold by Whisker, not Amazon. | $1.50 a lb | $30 at Whisker’s store |
| Drawer bags | Amazon Basics 13-gallon white kitchen bags, 90 White, 13 gallons. Whisker says white bags work best. | $0.17 a bag | $15.34 at Amazon |
| Whisker's bags | Whisker liners, 50 Made for the drawer. Sold by Whisker. | $0.70 a bag | $35 at Whisker’s store |
Amazon prices checked November 2, 2026. We read Whisker’s store prices on November 2, 2026 (regular price, before any subscription discount). We do not test litter; the pick follows what Whisker says works, then price.
What works in a Litter-Robot 4, and what to avoid
The Litter-Robot needs clumping litter: “Litter-Robot’s system requires clumping litter.” Whisker. The box sifts out the clumps and keeps the clean litter, so litter that does not clump, or comes as pellets, will not work.
On the Litter-Robot 4, color matters too. Whisker says white or see-through litter, which is most often crystal litter, “may impact the litter level and Drawer Full Indicator (DFI) accuracy” Whisker. That is why Pretty Litter is on the avoid list for the 4, even though it works in the older Litter-Robot 3.
| Litter | Whisker says |
|---|---|
| Tidy Cats Designed for Litter-Robot | Works Works. Whisker names it a best litter. “Specially formulated for Litter-Robot and The Perfect Cycle™ . Note that this litter features a revitalizing scent, but the fragrance is only activated by motion (i.e., when Litter-Robot cycles).” Whisker |
| Lit (Whisker’s own) | Works Works. Whisker names it a best litter. “Officially recommended litter, designed by Whisker specifically for Litter-Robot .” Whisker |
| Dr. Elsey’s clay | Works Works, Whisker says. “Dr. Elsey cat litter . Clay-based, will work in Litter-Robot.” Whisker |
| Pretty Litter and other white or clear crystal litter | Avoid Avoid on the Litter-Robot 4. It can throw off the litter and drawer-full readings. “Pretty Litter. Not recommended for Litter-Robot 4, 5/Pro, or EVO: Translucent or white-colored litter (most often seen in crystal litter) will impact the accuracy of litter and waste level readings.” Whisker |
| Tidy Cats Breeze | Avoid Avoid. Pellets do not sift. “Tidy Cats Breeze . Pellet-shaped. Will not sift properly in Litter-Robot.” Whisker |
| Feline Pine | Avoid Avoid. Pellets do not sift. “Feline Pine cat litter . Pellets, will not sift in Litter-Robot.” Whisker |
| World’s Best | Avoid Avoid. Whisker cites odor, sensor and bug reports. “World's Best cat litter . Corn-based, reports of stronger odor issues. Damages DFI/pinch quickly, mold, and increased chance of bug issues.” Whisker |
Whisker’s full list covers more brands. “Cat litters that are strictly absorbent, non-clumping, loose-clumping, newspaper-based, or wood-based pellets should NOT be used.” Whisker
Drawer bags: you do not need Whisker’s
Any bag that fits the waste drawer works. “Litter-Robot does not require special bags or liners for the waste drawer, but white bags work best. Customers often use 10 to 13-gallon white kitchen garbage bags or large white plastic grocery bags.” Whisker
Pick white. “Please note that waste level readings may be inaccurate when using a dark bag, especially when the drawer is empty.” Whisker And keep the bag low: “Make sure the bag does not come up past the top of the sides of the waste drawer, which can result in a false flashing “drawer full” light on the control panel.” Whisker
How many bags you use depends on your cats. Whisker says one cat usually needs the drawer emptied once a week, and two average-size cats about twice a week Whisker. That is about 52 bags a year for one cat:
| Bags | One cat | Two cats |
|---|---|---|
| Amazon Basics 13-gallon white kitchen bags | about $9 a year | about $18 a year |
| Whisker liners, 50-pack | about $36 a year | about $73 a year |
Bag cost a year = price per bag × 52 emptyings for one cat, × 2 for two cats. Whisker’s 50-pack at its regular price of $35.
How much litter to put in
Fill to the line inside the globe. “The optimal litter bed level inside Litter-Robot is at or just below the fill line inside the globe.” Whisker
Questions people ask
What is the best litter for the Litter-Robot 4?
Tidy Cats Designed for Litter-Robot, for most homes. Whisker names it and its own Lit as the two best litters for the Litter-Robot. Tidy Cats costs less per pound ($0.91 on Amazon against $1.50 for Lit at Whisker's regular price).
Can I use crystal litter or Pretty Litter in a Litter-Robot 4?
Whisker says no for Pretty Litter on the Litter-Robot 4. White or see-through crystal litter can throw off the litter level and drawer-full readings on the 4, the 5 and the EVO.
Can I use any clumping litter?
Most clumping clay works. Whisker lists brands like Dr. Elsey's as working. It says to avoid litter that does not clump, clumps loosely, or comes as paper or wood pellets.
Is Tidy Cats Designed for Litter-Robot scented?
Yes. Whisker says its scent is only released by motion, when the box cycles. If your cat does not like scent, use an unscented clay litter such as Dr. Elsey's Ultra Unscented. Whisker also says research shows most cats prefer unscented litter.
Do I need Whisker's waste drawer liners?
No. Whisker says any bag that fits works, and that white bags work best. Many owners use 10 to 13-gallon white kitchen bags. Dark bags can make the drawer-full reading wrong.
How often do I change the bag?
Whisker says about once a week for one cat and about twice a week for two average-size cats. Empty it when the app or the light on the box tells you to.
Sources
Whisker’s pages read November 2, 2026. Amazon listings and prices from Amazon’s product data, November 2, 2026. We did not test any litter or bag.
- www.litter-robot.com/blog/best-litter-for-litter-robot/
- www.litter-robot.com/support/article/litter-robot-waste-drawer-liner-installation-guide/
- www.litter-robot.com/blog/litter-robot-bags/
- www.litter-robot.com/litter-robot-waste-drawer-liners.html
- www.litterbox.com/lit-cat-litter.html
Next: Litter-Robot 4 · Litter-Robot 4 vs 5 · litter box for multiple cats
Tidy Cats Designed for Litter-RobotPrice as of November 2, 2026
$19.98 at Amazon