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Litter Box Size Calculator

Find the ideal litter box size for your cat based on veterinary research

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How would you like to calculate?

Size is estimated based on breed averages. For more accuracy, measure your cat directly.

Additional considerations

Recommends lower entry height for easier access

Recommends higher side walls to prevent spray

⚠️ Why Litter Box Size Matters

A litter box that's too small can cause serious health and behavioral problems. Research shows that space constraints are a leading cause of litter box avoidance.

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Feline Idiopathic Cystitis (FIC)

Chronic stress from cramped spaces can trigger bladder inflammation, causing painful urination and blood in urine.

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Urinary Crystals & Stones

Cats avoiding small boxes may "hold it", leading to concentrated urine and crystal formation.

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Inappropriate Elimination

Cats may start eliminating outside the box if they can't turn around or feel trapped inside.

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Chronic Stress

Cats can't complete natural elimination behaviors (digging, covering) in small boxes, causing ongoing anxiety.

📐 The Golden Rule

Length ≥ 1.5× Body Length

Backed by 120+ veterinary behavior studies, this rule ensures your cat can turn, dig, and cover comfortably.

Frequently Asked Questions

Cats need space to enter, turn around 180°, dig, eliminate, and cover - all without touching the sides. The 1.5x multiplier provides sufficient room for the turning radius and digging motion. This standard comes from veterinary behavioral research analyzing cat elimination patterns.
Measure from the tip of the nose to the base of the tail (where the tail meets the body). Do NOT include the tail itself. The tail is excluded because the 1.5x multiplier already accounts for space needed when the cat turns with its tail.
Research suggests open boxes are generally preferred. Covered boxes trap ammonia odors (cats smell 14x better than humans), block visual awareness (making cats feel vulnerable), and in multi-cat homes, can become ambush points. If you must use a covered box, clean it daily and ensure it's oversized.
Commercial "large" litter boxes are typically only 50-55cm long - far below what most cats need. Storage boxes like IKEA SAMLA (78cm) or Toyogo (80cm) provide adequate space at a fraction of the cost. They have flat bottoms for easier cleaning and high sides to prevent litter scatter.
The N+1 rule states you should have one more litter box than the number of cats (e.g., 2 cats = 3 boxes). More importantly, boxes should be placed in different locations - 3 boxes side by side count as one large box to cats. This prevents resource guarding and ensures every cat has access.
Maintain 5-8cm (2-3 inches) of litter depth. This allows cats to dig properly and ensures urine clumps form before reaching the bottom (preventing sticky residue). For senior cats with mobility issues, 3-4cm may be more comfortable.
Absolutely. If your cat stands with paws in the box but bottom hanging over the edge, or pees immediately upon entering without digging, size is likely the problem. Other signs include scratching the walls instead of litter, or rushing out immediately after elimination. Try a larger box before assuming it's a behavioral issue.

Perfect Box + Premium Litter = Happy Cat

Pair your ideal-sized box with Liger tofu litter for the ultimate elimination experience.

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