# Best Self-Cleaning Litter Box for Large Cats (2026) > The best self-cleaning litter boxes for big cats, compared on what matters: maker weight limits, entry size, interior height, step-up height and open tops. - Source: https://selfcleaninglitterboxguide.com/posts/best-self-cleaning-litter-box-for-large-cats/ - Markdown version: https://selfcleaninglitterboxguide.com/posts/best-self-cleaning-litter-box-for-large-cats.md - Last updated: 2026-11-12 --- - [Home](https://selfcleaninglitterboxguide.com/) - [Guides](https://selfcleaninglitterboxguide.com/guides/) - The Best Self-Cleaning Litter Box for Large Cats in 2026 Large cats # The Best Self-Cleaning Litter Box for Large Cats in 2026 Updated November 12, 2026 By [Self-Cleaning Litter Box Guide Editorial Team](https://selfcleaninglitterboxguide.com/about/) [How we research](https://selfcleaninglitterboxguide.com/how-we-research/) Prices are approximate and change often, so check the current price before you buy. ## Key takeaways - The **Litter-Robot 5** has the highest hooded limit here (30 lb) and the most headroom (17.5 in); the **Litter-Robot 4** shares its 15.75 × 15.75 in entry and is rated to 25 lb. - The **Neakasa M1** is rated for cats up to 33 lb and has no hood at all, which makes it the simplest fit for very large cats. - A weight limit isn't a fit guarantee. WIRED's 17-lb cat found the PuraMax 2 cramped, even though PETKIT lists it to 22 lb. - The AAFP says a box should be 1.5 times your cat's length from nose to base of tail, and that many commercial boxes are too small. - Check step-up height for heavy or older cats: about 10 in on the Purobot Max Pro 2 and 12 in on the SmartSpin. ## Our top picks - 1![Whisker Litter-Robot 5](https://selfcleaninglitterboxguide.com/_astro/whisker-litter-robot-5.JMut0Qu8_Z1BLhyu.webp)Best for the biggest cats: 3–30 lb, 15.75 in entry, 17.5 in interior height, about $799[Whisker Litter-Robot 5](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-5/)Rotating globe · 3–30 lb · up to 5 cats8.5**$$$**$PremiumPrice tier: Premium[Check price on Amazon](https://www.amazon.com/dp/B0HN8C8TFM?tag=selfcleaninglitterboxguide.com-20) - 2![Whisker Litter-Robot 4](https://selfcleaninglitterboxguide.com/_astro/whisker-litter-robot-4.CZhanV3w_12M27U.webp)Best overall for large cats: 3–25 lb, 15.75 in entry, 16.5 in interior height, about $699–749[Whisker Litter-Robot 4](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-4/)Rotating globe · 3–25 lb · up to 4 cats8.7**$$$**$PremiumPrice tier: Premium[Check price](https://www.amazon.com/dp/B0BH6MD3DJ?tag=selfcleaninglitterboxguide.com-20) - 3![Neakasa M1 Open-Top Self-Cleaning Litter Box](https://selfcleaninglitterboxguide.com/_astro/neakasa-m1.BQlFduq4_Z2r5bH9.webp)Best open-top for large cats: no hood, rated to 33 lb, about $360–450[Neakasa M1 Open-Top Self-Cleaning Litter Box](https://selfcleaninglitterboxguide.com/litter-boxes/neakasa-m1/)Open-top · 2.2–33 lb · cats: not stated8.3**$$**$$Mid-rangePrice tier: Mid-range[Check price](https://www.amazon.com/dp/B0DP8XYYKC?tag=selfcleaninglitterboxguide.com-20) - 4![PETKIT Purobot Max Pro 2](https://selfcleaninglitterboxguide.com/_astro/petkit-purobot-max-pro-2.tJpodhLt_Zt19WQ.webp)Best drum for big cats: WIRED's 17-lb cat used it easily, about $500–550[PETKIT Purobot Max Pro 2](https://selfcleaninglitterboxguide.com/litter-boxes/petkit-purobot-max-pro-2/)Tilting drum · 3.3–22 lb · cats: not stated8.6**$$**$$Mid-rangePrice tier: Mid-range[Check price](https://www.amazon.com/dp/B0DFYLFFG1?tag=selfcleaninglitterboxguide.com-20) ### On this page 8 sections - [The shortlist](#the-shortlist) - [Weight limits at a glance](#weight-limits-at-a-glance) - [Four things to check for a big cat](#four-things-to-check-for-a-big-cat) - [Our picks](#our-picks) - [Boxes we’d skip for a large cat](#boxes-wed-skip-for-a-large-cat) - [Safety still matters with big cats](#safety-still-matters-with-big-cats) - [How to pick](#how-to-pick) - [FAQ](#faq) ## Before you choose - [The Best Open-Top Self-Cleaning Litter Boxes of 2026](https://selfcleaninglitterboxguide.com/posts/best-open-top-self-cleaning-litter-box/) - [Neakasa M1 vs Litter-Robot 4: Open-Top or Globe?](https://selfcleaninglitterboxguide.com/posts/neakasa-m1-vs-litter-robot-4/) - [Litter-Robot 5 vs Litter-Robot 4 vs EVO: Which Litter-Robot to Buy in 2026](https://selfcleaninglitterboxguide.com/posts/litter-robot-5-vs-litter-robot-4-vs-evo/) Big cats are where self-cleaning litter boxes most often disappoint. A box can be rated for your cat’s weight and still be too small to turn around in, and a tall step-up that a young cat hops over can put off a heavy older one. This guide picks the boxes that actually suit large cats and explains which numbers to check. We haven’t tested these boxes ourselves. The picks are based on maker specs, Amazon listing text and independent testing, mostly by WIRED and Tom’s Guide, and we name the outlet whenever a test result appears. Prices are typical street prices from dated sources, so check today’s price. ## The shortlist | Box | Maker weight range | Entry | Interior height | Step-up | Price | | --- | --- | --- | --- | --- | --- | | [Litter-Robot 5](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-5/) | 3–30 lb | 15.75 × 15.75 in | 17.5 in | Not published | ~$799 | | [Litter-Robot 4](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-4/) | 3–25 lb | 15.75 × 15.75 in | 16.5 in | Elevated step (Tom’s Guide) | ~$699–749 | | [Neakasa M1](https://selfcleaninglitterboxguide.com/litter-boxes/neakasa-m1/) | 2.2–33 lb | Open top (M1 Plus: 17 × 16.5 in, WIRED) | No hood | 13.86 in entry height (Neakasa) | ~$360–450 | | [Purobot Max Pro 2](https://selfcleaninglitterboxguide.com/litter-boxes/petkit-purobot-max-pro-2/) | 3.3–22 lb | 10.51 × 10.74 in | Not published | About 10 in | ~$500–550 | | [ScoopFree SmartSpin](https://selfcleaninglitterboxguide.com/litter-boxes/petsafe-scoopfree-smartspin/) | 2.5–25 lb | Not published | Not published | 12 in | ~$340–400 | ## Weight limits at a glance The chart shows the cat weights each maker allows in automatic mode. For a big cat, look at the right end of each bar. Which cat weights each box allows (lb) Maker ranges for automatic mode. Below the left end, the sensors may not notice your cat; hatched bars have no published minimum. Hooded globe / drum Open-top Rake / other [Leo's Loo Too 1–20](https://selfcleaninglitterboxguide.com/litter-boxes/casa-leo-leos-loo-too/)[Neakasa M1 2.2–33](https://selfcleaninglitterboxguide.com/litter-boxes/neakasa-m1/)[ScoopFree SmartSpin 2.5–25](https://selfcleaninglitterboxguide.com/litter-boxes/petsafe-scoopfree-smartspin/)[Litter-Robot 5 3–30](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-5/)[Litter-Robot 4 3–25](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-4/)[Litter-Robot EVO 3–19](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-evo/)[Purobot Ultra 3.3–22](https://selfcleaninglitterboxguide.com/litter-boxes/petkit-purobot-ultra/)[Purobot Max Pro 2 3.3–22](https://selfcleaninglitterboxguide.com/litter-boxes/petkit-purobot-max-pro-2/)[PuraMax 2 3.3–22](https://selfcleaninglitterboxguide.com/litter-boxes/petkit-puramax-2/)[Furbulous Self-Packing 3.3–22](https://selfcleaninglitterboxguide.com/litter-boxes/furbulous-self-packing/)[Lesure Open-Top 3.3–18](https://selfcleaninglitterboxguide.com/litter-boxes/lesure-open-top/)[ELS PET Orbitie ?–21](https://selfcleaninglitterboxguide.com/litter-boxes/els-pet-orbitie/)[ScoopFree Classic ?–15](https://selfcleaninglitterboxguide.com/litter-boxes/petsafe-scoopfree-crystal-classic/)[ScoopFree Crystal Smart ?–?](https://selfcleaninglitterboxguide.com/litter-boxes/petsafe-scoopfree-crystal-smart/) 05101520253035 Kittens under the minimum should use the box with automatic cleaning off. Check your own cat in the [safety checker](https://selfcleaninglitterboxguide.com/tools/cat-safety-checker/). ## Four things to check for a big cat ### 1. The maker’s maximum weight, and whether sources agree Maximums run from 15 lb on the ScoopFree Classic to 33 lb on the Neakasa M1. Some makers contradict themselves. PETKIT’s FAQ lists the PuraMax 2 at 3.3–22 lb, while PETKIT’s own buying guide says up to 18 lb, and WIRED lists 3.5–18 lb. The Lesure’s Amazon listing says 18 lb in its headline and 15 lb in its FAQ. When figures disagree, use the lower one. ### 2. Entry size The entry is where big cats get stuck, literally or not. The Litter-Robot 4 and 5 share a 15.75 × 15.75 in entry, and the EVO’s is 14.85 × 14.85 in. The PuraMax 2’s is 10.04 × 7.87 in by PETKIT’s figures, and WIRED’s 17-lb cat found it cramped. The Purobot Max Pro 2’s 10.51 × 10.74 in entry is 43% larger, per PETKIT, and the same 17-lb cat used it easily. Open-top boxes skip the question. ### 3. Room inside The AAFP recommends a box 1.5 times your cat’s length from nose to base of tail and says many commercial boxes are too small. Self-cleaning boxes rarely publish usable interior length, so interior height is the best proxy we have: 17.5 in on the Litter-Robot 5, 16.5 in on the Litter-Robot 4, 14.5 in on the EVO. WIRED’s 12-lb cat found Leo’s Loo Too cramped, and cats.com says the Furbulous is too small for large cats. Measure your cat and enter the length in the [safety checker](https://selfcleaninglitterboxguide.com/tools/cat-safety-checker/#weight=18&length=20) to see which boxes fit. ### 4. Step-up height Heavy cats and older cats with stiff joints can balk at a high entry. The Purobot Max Pro 2 entry sits about 10 in off the floor, and PetSafe says the SmartSpin sits 12 in from the ground. Neakasa lists the M1’s entry height as 13.86 in. Whisker sells a ramp for the Litter-Robot 4 ($65 at Whisker), and WIRED recommends a ramp for the Litter-Robot 5. ## Our picks ### Whisker Litter-Robot 5: Best for the biggest cats The [Litter-Robot 5](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-5/) has the highest limit of any hooded box here, 3 to 30 lb, and the most headroom at 17.5 in. It shares the Litter-Robot 4’s 15.75 × 15.75 in entry and adds multiple lasers plus weight sensors and WasteID, which separates urine and stool visits. It’s rated for up to five cats. The downsides are price and maturity. It costs about $799 for the robot at Whisker before Whisker+, which WasteID and cat ID need (about $80 a year, per WIRED), and both features were intermittent in WIRED’s first four months. WIRED reviewed it but didn’t make it a pick, so we can’t cite WIRED’s open-entry criterion for this model. [Check the Litter-Robot 5 price](https://www.amazon.com/dp/B0HN8C8TFM?tag=selfcleaninglitterboxguide.com-20). ### Whisker Litter-Robot 4: Best overall for large cats The [Litter-Robot 4](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-4/) is the better buy unless your cat is over 25 lb. Same entry as the LR5, 16.5 in of interior height, a laser curtain plus weight sensors, and a place among WIRED’s picks, all of which stay open while cycling. Tom’s Guide notes the elevated step and the interior night light, and found it still holding up after more than a year, though it sometimes squeaked and needs regular maintenance. WIRED’s long-term unit began sensing ghost cats after about two years, and sometimes reported a full drawer when it was half full. Whisker says the drawer may need emptying as rarely as once every 8 days. About $699–749. [Check the Litter-Robot 4 price](https://www.amazon.com/dp/B0BH6MD3DJ?tag=selfcleaninglitterboxguide.com-20), or see [Neakasa M1 vs Litter-Robot 4](https://selfcleaninglitterboxguide.com/posts/neakasa-m1-vs-litter-robot-4/). ### Neakasa M1: Best open-top for large cats The [Neakasa M1](https://selfcleaninglitterboxguide.com/litter-boxes/neakasa-m1/) has no hood, so there’s no entry to squeeze through and no ceiling to hunch under. Neakasa recommends it for cats from 2.2 to 33 lb and says the open top has almost no hard weight limit. WIRED measured the M1 Plus opening at 17 × 16.5 in. Tom’s Guide’s cats used it 51 times in one week, more than any other box in that test. Big cats in an open box can mean more scatter: Tom’s Guide and WIRED both found the M1 flings litter, so put a large mat under it. WIRED didn’t recommend the original M1 because of controversies over safety, faulty sensors and counterfeit models, and picked the M1 Plus. Buy from Neakasa’s own storefront. About $360–450. [Check the Neakasa M1 price](https://www.amazon.com/dp/B0DP8XYYKC?tag=selfcleaninglitterboxguide.com-20), or the [M1 Plus](https://www.amazon.com/dp/B0CSKBWBF6?tag=selfcleaninglitterboxguide.com-20). ### PETKIT Purobot Max Pro 2: Best drum for big cats If you want PETKIT’s compact drum design, the [Purobot Max Pro 2](https://selfcleaninglitterboxguide.com/litter-boxes/petkit-purobot-max-pro-2/) is the one for big cats. WIRED’s 17-lb cat used it easily, where the same cat found the PuraMax 2 cramped. It adds a 1080p, 210° camera and an 8 L bin rated for up to 17 days with one cat. Its maker limit is 22 lb, lower than the Whisker and Neakasa boxes, and the entry sits about 10 in off the floor. WIRED found the app crowded with ads. PETKIT’s guidance is cats over 3.3 lb and older than 6 months, and it asks for litter with granules under 0.5 in. About $500–550. [Check the Purobot Max Pro 2 price](https://www.amazon.com/dp/B0DFYLFFG1?tag=selfcleaninglitterboxguide.com-20). ### Worth a look: PetSafe ScoopFree SmartSpin The [SmartSpin](https://selfcleaninglitterboxguide.com/litter-boxes/petsafe-scoopfree-smartspin/) is rated for cats up to 25 lb and costs about $340–400. WIRED says it works surprisingly well. PetSafe doesn’t publish its entry size, it relies on a weight detector alone, and it sits 12 in off the floor, so we’d only consider it for a large, agile cat. [Check the SmartSpin price](https://www.amazon.com/dp/B0D4GHS7V6?tag=selfcleaninglitterboxguide.com-20). ## Boxes we’d skip for a large cat - **[PETKIT PuraMax 2](https://selfcleaninglitterboxguide.com/litter-boxes/petkit-puramax-2/):** WIRED’s 17-lb cat found the entry cramped. Fine for average cats. - **[Litter-Robot EVO](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-evo/):** capped at 19 lb. - **[Leo’s Loo Too](https://selfcleaninglitterboxguide.com/litter-boxes/casa-leo-leos-loo-too/):** Tom’s Guide calls its opening the smallest it tested, and WIRED’s 12-lb cat found it cramped. - **[Lesure Open-Top](https://selfcleaninglitterboxguide.com/litter-boxes/lesure-open-top/):** open, but the listing’s limit is 15 or 18 lb. - **[ScoopFree Crystal Classic](https://selfcleaninglitterboxguide.com/litter-boxes/petsafe-scoopfree-crystal-classic/):** designed for cats up to 15 lb. - **[Furbulous Self-Packing](https://selfcleaninglitterboxguide.com/litter-boxes/furbulous-self-packing/):** cats.com found it too small for large cats, and its design could trap a cat if the sensors fail. ## Safety still matters with big cats Weight minimums exist because sensors can miss light cats, and a big cat clears all of them, so fit is the main issue. But if a smaller cat or kitten shares the box, every cat has to be above the maker’s minimum: 3 lb for Whisker, 3.3 lb for PETKIT, 2.2 lb for Neakasa. Below that, keep automatic cleaning off. Prefer boxes whose entrance stays open while cycling; WIRED won’t recommend models that close completely. More in [are self-cleaning litter boxes safe?](https://selfcleaninglitterboxguide.com/posts/are-self-cleaning-litter-boxes-safe/) ## How to pick - **Cat over 25 lb:** Neakasa M1 (open) or Litter-Robot 5 (hooded). - **Cat 15–25 lb, want the most proven box:** Litter-Robot 4. - **Cat up to about 22 lb, want a camera:** Purobot Max Pro 2. - **Cat hates hoods:** Neakasa M1. See [best open-top self-cleaning litter box](https://selfcleaninglitterboxguide.com/posts/best-open-top-self-cleaning-litter-box/). Filter the full lineup with the [litter box matcher](https://selfcleaninglitterboxguide.com/tools/litter-box-matcher/#size=large), or compare entry sizes for every model in the [comparison chart](https://selfcleaninglitterboxguide.com/litter-boxes/). ## Don't guess. Calculate. - [🐾 Safety checker](https://selfcleaninglitterboxguide.com/tools/cat-safety-checker/): which boxes fit your cat - [💵 Cost calculator](https://selfcleaninglitterboxguide.com/tools/litter-box-cost-calculator/): 1-, 3- and 5-year totals - [🎯 Litter box matcher](https://selfcleaninglitterboxguide.com/tools/litter-box-matcher/): ranked for your home - [📊 Compare every box](https://selfcleaninglitterboxguide.com/litter-boxes/): sortable spec table ## Frequently asked questions ### What is the best self-cleaning litter box for a large cat? For a hooded box, the Whisker Litter-Robot 5 (3–30 lb, 15.75 × 15.75 in entry, 17.5 in interior height) or the cheaper Litter-Robot 4 (3–25 lb, same entry, 16.5 in interior). For an open box, the Neakasa M1, which Neakasa rates for cats up to 33 lb. ### Is the PETKIT PuraMax 2 big enough for a large cat? Often not. PETKIT lists its entry at 10.04 × 7.87 in, and WIRED's 17-lb cat found it cramped. PETKIT's own maximum-weight figures also disagree (18 vs 22 lb). The Purobot Max Pro 2 has a 43% larger entry, and WIRED's 17-lb cat used it easily. ### How big should a litter box be for a big cat? The AAFP's guidance is 1.5 times your cat's length from nose to the base of the tail, and it notes that many commercial boxes are too small. Self-cleaning boxes rarely list their usable interior length, so use entry size, interior height and the maker's weight limit as your guide, and check reviewers' experience with big cats. ### Do large cats trigger self-cleaning litter boxes safely? Weight minimums exist because sensors can miss light cats. A big cat is well above every minimum, so fit is the main question. Safety still matters if a smaller cat or kitten shares the box: every cat using it should be above the maker's minimum weight, or automatic cleaning should stay off. ## Sources - [Whisker: Litter-Robot 5](https://www.litter-robot.com/litter-robot-5.html) · checked 2026-11-12 — Cats 3–30 lb, up to five cats; 15.75 × 15.75 in entry; 17.5 in interior height. - [Whisker: Litter-Robot 4](https://www.litter-robot.com/litter-robot-4.html) · checked 2026-11-12 — Cats 3–25 lb; 15.75 × 15.75 in entry; 16.5 in interior height. - [Whisker: Litter-Robot EVO](https://www.litter-robot.com/litter-robot-evo.html) · checked 2026-11-12 — Cats 3–19 lb; 14.85 × 14.85 in entry; 14.5 in interior height. - [Neakasa: M1 product page](https://neakasa.com/products/neakasa-m1-cat-litter-box) · checked 2026-11-12 — Recommended for cats 2.2–33 lb with almost no hard weight limit; entry height 13.86 in. - [PETKIT: Purobot Max Pro 2](https://www.petkit.com/products/purobot-max-pro-2-automatic-cat-litter-box-with-ai-camera) · checked 2026-11-12 — Entrance 10.51 × 10.74 in, 43% wider than before; cats 3.3–22 lb. - [WIRED: The Best Automatic Litter Boxes](https://www.wired.com/gallery/best-automatic-cat-litter-boxes/) · checked 2026-11-12 — A 17-lb cat found the PuraMax 2 opening cramped but used the Purobot Max Pro 2 easily; a 12-lb cat found Leo's Loo Too cramped; the M1 Plus is rated up to 33 lb. - [PetSafe: ScoopFree SmartSpin](https://www.petsafe.com/product/scoopfree-smartspin-self-cleaning-litter-box/) · checked 2026-11-12 — For cats up to 25 lb; the box sits 12 in from the ground. - [AAFP/ISFM house-soiling client guide](https://catvets.com/wp-content/uploads/2024/01/HouseSoiling-B&W.pdf) · checked 2026-11-12 — Litter boxes should be 1.5 times the cat's length from nose to base of tail; many commercial boxes are too small. ## Get new guides by e-mail One short e-mail when Self-Cleaning Litter Box Guide publishes a new guide. No spam, no sharing your address, and you can unsubscribe in one click. E-mail address New posts only · Unsubscribe anytime · [Privacy](https://selfcleaninglitterboxguide.com/privacy/) Our #1 pick Best for the biggest cats: 3–30 lb, 15.75 in entry, 17.5 in interior height, about $799 ![Whisker Litter-Robot 5](https://selfcleaninglitterboxguide.com/_astro/whisker-litter-robot-5.JMut0Qu8_EdAxV.webp) ### [Whisker Litter-Robot 5](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-5/) 8.5 - Rotating globe - 3–30 lb - Up to 5 cats Big and multi-cat households (up to five cats, up to 30 lb) that want health data on top of hands-off scooping. $$$$ Premium Price tier: Premium typical street price; check Amazon for today's [Check price on Amazon](https://www.amazon.com/dp/B0HN8C8TFM?tag=selfcleaninglitterboxguide.com-20)[Read the full review](https://selfcleaninglitterboxguide.com/litter-boxes/whisker-litter-robot-5/) [🐾 Safe for your cat? Check weight limits, kitten rules and cats per box in 20 seconds.](https://selfcleaninglitterboxguide.com/tools/cat-safety-checker/)[💵 What will it really cost? Liners, trays and litter over five years, model by model.](https://selfcleaninglitterboxguide.com/tools/litter-box-cost-calculator/) ## Keep reading [Open-top ### The Best Open-Top Self-Cleaning Litter Boxes of 2026 The best open-top self-cleaning litter boxes: Neakasa M1 vs M1 Plus vs Lesure, plus ScoopFree rake boxes as alternatives, with scatter, mat and safety advice. Updated Nov 12, 2026](https://selfcleaninglitterboxguide.com/posts/best-open-top-self-cleaning-litter-box/)[Head-to-head ### Neakasa M1 vs Litter-Robot 4: Open-Top or Globe? Neakasa M1 vs Litter-Robot 4: open-top vs globe, Tom's Guide's usage counts, M1 vs M1 Plus vs Lite, counterfeit listings, litter scatter and fit for large cats. Updated Nov 12, 2026](https://selfcleaninglitterboxguide.com/posts/neakasa-m1-vs-litter-robot-4/)[Which to buy ### Litter-Robot 5 vs Litter-Robot 4 vs EVO: Which Litter-Robot to Buy in 2026 Litter-Robot 5 vs 4 vs EVO: weight and cat limits, entry sizes, sensors, WasteID and Whisker+, prices and running costs, and which Litter-Robot fits your home. Updated Nov 12, 2026](https://selfcleaninglitterboxguide.com/posts/litter-robot-5-vs-litter-robot-4-vs-evo/) Best for the biggest cats: 3–30 lb, 15.75 in entry, 17.5 in interior height, about $799 Litter-Robot 5 $$$$ Premium Price tier: Premium [Check price](https://www.amazon.com/dp/B0HN8C8TFM?tag=selfcleaninglitterboxguide.com-20)