Rabbit Diet Guide: The 80-15-5 Rule for a Healthy Bunny

A proper diet is the most important factor in preventing GI stasis, dental disease, and obesity in rabbits. The 80-15-5 rule makes it simple.

The 80-15-5 Rule

80% unlimited grass hay, 15% fresh leafy greens, 5% fortified pellets. Treats: occasional fruit (1 tsp per 2 lbs body weight, 1-2x per week max).

Hay: 80% of Diet, Always Available

Timothy hay (best all-around for adult rabbits), orchard grass (softer, good for picky eaters), meadow hay (variety), oat hay (treat hay — higher calorie). Alfalfa hay: for growing rabbits (under 6 months), pregnant/lactating does. Too high in calcium for adult rabbits — causes bladder sludge.

Fresh Greens: 15% of Diet, Daily

Safe daily greens (2 cups per 6 lbs body weight): romaine lettuce, green leaf lettuce, cilantro, parsley, basil, dill, mint, dandelion greens, carrot tops, bok choy, kale (rotate, not daily due to calcium), spinach (rotate, not daily due to oxalates). Introduce new greens one at a time. If soft stool develops, reduce that vegetable. Always wash thoroughly.

Pellets: 5% of Diet, Measured

1/4 cup per 5 lbs body weight daily. Choose timothy-based pellets (not alfalfa for adults). Plain pellets only — no seeds, nuts, dried fruit, or colored pieces. Recommended brands: Oxbow Essentials, Small Pet Select.

Toxic Foods — NEVER Feed

Iceberg lettuce (causes diarrhea), avocado (toxic), chocolate, onion, garlic, rhubarb, tomato leaves, potato, bread/crackers/cereal, yogurt drops, seeds, nuts, honey sticks, and any human processed food. Treats marketed for rabbits in pet stores are often unhealthy — stick to small fruit portions as treats.

Water

Unlimited fresh water, changed daily. Bowls are better than bottles (more natural drinking position, rabbits drink more). Some rabbits prefer both. Clean weekly.

The Transition Rule

Introduce new foods gradually over 7-10 days. A rabbit's gut microbiome is sensitive. Sudden changes trigger GI stasis.

Why Diet Prevents Most Rabbit Health Problems

The fiber in hay wears down continuously growing teeth (prevents dental disease). Fiber keeps the gut moving (prevents GI stasis). Low-calorie hay prevents obesity. A hay-based diet is the single most important thing you can do for your rabbit's health.