Quoted from manufacturer documents

Litter compatibility matrix

Each cell reflects what the manufacturer actually writes. Nothing here is inferred from particle size, from a similar model, or from what a retailer claims. Where the manual and the product page disagree, the manual controls and the disagreement is recorded.

Clumping clay →

21 supported0 with conditions3 excluded20 not stated

Tofu →

5 supported4 with conditions11 excluded24 not stated

Mixed

6 supported4 with conditions4 excluded30 not stated

Crystal

3 supported6 with conditions6 excluded29 not stated

Pine pellet

0 supported2 with conditions13 excluded29 not stated

Other pellet

0 supported4 with conditions14 excluded26 not stated

Supported Supported with conditions Not supported / not recommended Manufacturer does not state

28 documented-tier products. Blank cells are not gaps in this index — they are values the manufacturer does not publish.
Product	Clumping clay	Tofu	Mixed	Crystal	Pine pellet	Other pellet
Amazon Basics Automatic Self-Cleaning Litter Box (SMARTO M500) Quoted evidence No manufacturer specification page exists for this product; no litter compatibility statement located. Retailer-declared	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
BISSELL CleanWell 4393 Quoted evidence No litter compatibility statement published on the manufacturer product page. Manufacturer	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
CATLINK Scooper Open-X Quoted evidence 'Compatible with any clumping cat litter' — blanket claim, no exclusions or particle limit published for this model. Retailer-declared	YesSupported	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
CATLINK Scooper Young Pro-X Quoted evidence Small-particle clumping litters; particles must pass the sift filter. Explicitly not recommended: pure tofu and long-strip tofu. Excluded: strictly absorbent, non-clumping, loose-clumping, newspaper-based, wood pellets. Manufacturer	YesSupported	Not rec.Not recommended by manufacturer	Cond.Supported with conditions	—Manufacturer does not state	NoNot supported	NoNot supported
Casa Leo Leo's Loo Too Quoted evidence MANUAL: 'Use only clay clumping cat litter that absorbs moisture.' Manual also instructs adding 4.5-5.5 kg of litter and not filling beyond the indicator sticker. Manual	YesSupported	NoNot supported	NoNot supported	NoNot supported	NoNot supported	NoNot supported
CatGenie CatGenie A.I. Quoted evidence 'NEVER use cat litter in the CatGenie.' Requires proprietary Washable Granules only. Manufacturer	NoNot supported	NoNot supported	NoNot supported	NoNot supported	NoNot supported	NoNot supported
HHOLOVE Automatic Litter Box Pro (60 L) Quoted evidence No litter compatibility statement published on the manufacturer product page. Manufacturer	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
HomerunPet CS106 Quoted evidence Compatible: clumping clay, tofu, cassava, cassava-tofu mix, tofu-bentonite mix. Two filter types supplied (large-pore and small-pore). No exclusion list and no numeric particle limit published. Manufacturer	YesSupported	YesSupported	YesSupported	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
Neakasa M1 Plus Quoted evidence Recommends fast-clumping scoopable bentonite/mineral litter. Excludes highly absorbent, non-clumping, loosely clumping, newspaper and wood pellet litters. Particle limit: up to 3 mm diameter and 10 mm length — tofu/mixed only qualify if within that limit. Manufacturer	YesSupported	Cond.Supported with conditions	Cond.Supported with conditions	NoNot supported	NoNot supported	NoNot supported
Neakasa M1 Plus Lite Quoted evidence Manufacturer page compares M1 and M1 Lite in FAQ only; no separate Lite specification block published. Manufacturer	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
PETKIT Pura X	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
PETKIT PuraMax 2 (P9902) Quoted evidence MANUAL: 'Do not use large particles of cat litter larger than 1.2 cm in length and 3 mm in diameter.' 'The standard litter sitter is suitable for tofu cat litter and mixed cat litter; the honeycomb fine litter sitter is suitable for mineral cat litter.' Manual	YesSupported	Cond.Supported with conditions	Cond.Supported with conditions	—Manufacturer does not state	—Manufacturer does not state	Cond.Supported with conditions
PETKIT Purobot Max 3 (P9906) Quoted evidence '99% of clumping litters including clay, tofu, corn, bentonite'. Crystal only via a separate Crystal Duo model. No particle limit published for this model. Manufacturer	YesSupported	YesSupported	YesSupported	NoNot supported	—Manufacturer does not state	—Manufacturer does not state
PETKIT Purobot Max Pro 2 Quoted evidence MANUAL: 'The size of cat litter should not exceed 12 mm (0.47 in) in length and 3 mm (0.12 in) in diameter.' A dedicated litter sitter is described as 'exclusive for tofu cat litter and mixed cat litter'. Manual	YesSupported	Cond.Supported with conditions	YesSupported	—Manufacturer does not state	NoNot supported	Cond.Supported with conditions
PETKIT Purobot Ultra (P9903) Quoted evidence MANUAL: two litter sitters supplied - P99031 'suitable for tofu cat litter and mixed cat litter'; P99032 'suitable for fine granular cat litter such as mineral cat litter and bentonite'. Product page publishes a particle limit of length <=12 mm, diameter <=3 mm. Manual	YesSupported	YesSupported	YesSupported	—Manufacturer does not state	—Manufacturer does not state	Cond.Supported with conditions
PETLIBRO Luma Quoted evidence Compatible: 'clumping, tofu, and mixed litters'. Excluded: 'non-clumping (crystal, pine) or ultra-fine litters (grass seed, cassava)'. Manufacturer	YesSupported	YesSupported	YesSupported	NoNot supported	NoNot supported	NoNot supported
PetSafe ScoopFree Crystal Classic Quoted evidence Same ScoopFree crystal-tray architecture as Crystal Pro. Retailer-declared	NoNot supported	NoNot supported	NoNot supported	YesSupported	NoNot supported	NoNot supported
PetSafe ScoopFree Crystal Pro Quoted evidence System is designed around PetSafe ScoopFree disposable/reusable crystal litter trays; the rake mechanism is specified for crystal litter. Retailer-declared	NoNot supported	NoNot supported	NoNot supported	YesSupported	NoNot supported	NoNot supported
PetSafe ScoopFree OpenSky Quoted evidence MANUAL (outranks the product page's 'most clumping litter types'): 'Litter with larger pellets, such as pine or tofu litter, may not be compatible with the litter box.' Manual	YesSupported	Not rec.Not recommended by manufacturer	—Manufacturer does not state	NoNot supported	Not rec.Not recommended by manufacturer	Not rec.Not recommended by manufacturer
PetSafe ScoopFree SmartSpin Quoted evidence MANUAL (outranks the product page's blanket 'compatible with any litter'): 'Litter with larger pellets, such as tofu litter, may not be compatible with the litter box.' Litter must not be filled beyond the MAX fill line. Manual	YesSupported	Not rec.Not recommended by manufacturer	—Manufacturer does not state	Cond.Supported with conditions	—Manufacturer does not state	Not rec.Not recommended by manufacturer
PetSnowy SNOW+ Quoted evidence Compatible: 'all clumping litter (preferably clay), tofu, pine, and crystal litter'. Excluded: non-clumping, newspaper-based, absorbent wood pellet litter, absorption-only designs. NOTE: 'pine' is listed as compatible while 'absorbent wood pellet' is excluded — the manufacturer does not reconcile these. Manufacturer	YesSupported	YesSupported	YesSupported	YesSupported	Cond.Supported with conditions	NoNot supported
Petcove PurrTek Max Quoted evidence 'Works with any clumping litter' (brand shop copy). A sibling model, PurrTek Light, states quick-clumping bentonite clay only, no pellets/crystals — the brand's statements are not consistent across models. Retailer-declared	YesSupported	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
Popur X5 Quoted evidence 'Most clumping cat litter will work'; low-dust, lightweight, fast-absorbing, hard-clumping preferred. PrettyLitter crystals work; powder-like or small-particle crystal is fine; marble-like crystal is incompatible. Pellets: 3 mm or less diameter, 20 mm or less average length. Litter capacity 7-12 L. Manufacturer	YesSupported	Cond.Supported with conditions	Cond.Supported with conditions	Cond.Supported with conditions	Cond.Supported with conditions	Cond.Supported with conditions
Whisker Litter-Robot 3 Connect Quoted evidence 'Works with almost any clumping litter' (marketplace listing title, not a manufacturer spec page) Retailer-declared	YesSupported	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state	—Manufacturer does not state
Whisker Litter-Robot 4 Quoted evidence MANUAL (outranks product page): 'Never put anything in the unit other than clumping litter or litter beads and crystals that are small enough to pass through the screen.' Translucent/white litter may impact LitterLevel and Drawer Full Indicator accuracy. Lightweight litters such as corn or wheat 'may not pass through the screen effectively'. Do not work: strictly absorbent, non-clumping or loose-clumping, newspaper-based, pine-based, and absorbent wood pellet litter. Manual	YesSupported	Not rec.Not recommended by manufacturer	—Manufacturer does not state	Cond.Supported with conditions	NoNot supported	NoNot supported
Whisker Litter-Robot 5 Quoted evidence MANUAL (outranks product page, and resolves the conflict between the LR5 and LR5 Pro product pages): 'Never put anything in the unit other than clumping litter or litter beads and crystals that are small enough to pass through the screen. Translucent or white-colored litter (most often seen in crystal litter) may impact the LitterLevel and Drawer Full Indicator (DFI) accuracy.' Manual	YesSupported	NoNot supported	—Manufacturer does not state	Cond.Supported with conditions	NoNot supported	NoNot supported
Whisker Litter-Robot 5 Pro Quoted evidence MANUAL (outranks product page, and resolves the conflict between the LR5 and LR5 Pro product pages): 'Never put anything in the unit other than clumping litter or litter beads and crystals that are small enough to pass through the screen. Translucent or white-colored litter (most often seen in crystal litter) may impact the LitterLevel and Drawer Full Indicator (DFI) accuracy.' Manual	YesSupported	NoNot supported	—Manufacturer does not state	Cond.Supported with conditions	NoNot supported	NoNot supported
Whisker Litter-Robot EVO Quoted evidence MANUAL: clumping litter, or beads and crystals small enough to pass through the screen; translucent/white litter may impact Drawer Full Indicator accuracy. 'DO NOT use litters that are strictly absorbent, non-clumping, loose-clumping, newspaper-based, or wood-based pellets.' Manual	YesSupported	NoNot supported	—Manufacturer does not state	Cond.Supported with conditions	NoNot supported	NoNot supported

Absence as a finding

The budget tier publishes almost nothing

15 of the 16 budget and legacy records in this index carry no manufacturer litter guidance at all. Publishing a grid of dashes for them would imply we had looked and found ambiguity. We looked and found nothing published.

Those products account for a large share of the units sold in this category. If you buy one, the manufacturer is unlikely to tell you which litter it can handle. The full evidence →