What Can Chickens Eat?

Chickens are omnivores and will try almost anything — but a handful of common foods are genuinely toxic. Here's a sourced verdict on 32 foods people ask about most.

Reviewed against extension and veterinary guidance · Last reviewed July 2026

Never feed these

chocolate, avocado, onions, rhubarb — plus anything mouldy, alcoholic, caffeinated, or heavily salted.

These aren't "probably fine in small amounts" foods. Avocado and chocolate in particular can kill a bird outright.

Safe to feed

In moderation

Only when prepared

Do not feed

How treats fit into a chicken's diet

The single most useful rule is the 90/10 rule: at least 90% of what your flock eats should be balanced layer feed, with treats and kitchen scraps capped at roughly 10%. Layer feed is engineered to deliver the protein, calcium, and micronutrients that eggshells and feathers are made of. Treats are fun and useful for taming and boredom relief, but every handful of corn or bread displaces the feed doing the actual work — and that shows up as thinner shells and fewer eggs.

Ten percent is less than most people picture. A dozen hens eat about 3 lb of feed a day, so their entire treat budget is roughly 4.8 oz between them — not each. The chicken treat calculator turns the rule into a number for your flock size.

Chickens have no teeth. They grind everything in the gizzard using grit — small stones they swallow deliberately. Free-ranging birds find their own; a flock confined to a run needs insoluble grit on offer whenever they're eating anything other than feed. Skip it and even a perfectly safe treat can back up a crop.

Introduce anything new in small amounts and check the droppings the next day — that's the fastest signal something disagreed with them. And two rules that beat every list on this page:never feed mouldy food (some moulds produce mycotoxins that kill birds), and skip anything heavily salted, sugary, or processed. Chickens are small; a portion of salt that's trivial for you is not trivial for a 5 lb bird.

Related calculators

Sources

Verdicts follow established poultry nutrition and veterinary toxicology — the toxic compounds named here (persin, theobromine, solanine, thiosulphate, phytohaemagglutinin, oxalic acid) are documented, not folklore. Last reviewed July 2026.