Can chickens eat eggshells? Yes – and feeding eggshells back to your hens is one of the simplest, cheapest ways to top up the calcium that laying hens need for strong, healthy eggs. With a little care in how you prepare them, those shells you would normally bin become a free, nutritious calcium supplement straight from your kitchen.
Short answer: Save your eggshells, dry them, crush them so they are no longer recognisable as eggs, and offer them to your hens free-choice (separately from their feed). The calcium helps your laying hens produce strong eggshells and keeps their skeletons healthy.
Why do laying hens need extra calcium?
A laying hen puts a remarkable amount of calcium into every egg she produces. The eggshell itself is almost pure calcium carbonate, and a hen laying close to an egg a day draws heavily on her body's calcium reserves to make each one. If she does not get enough calcium from her diet, you may start to see thin, soft or misshapen shells – and over time she will pull calcium from her own bones, which is not good for her long-term health.
Most good-quality layers' pellets already contain added calcium, so a balanced feed does much of the work. But offering a supplementary calcium source – such as crushed eggshell or oyster shell – lets each hen top up exactly as much as she needs, when she needs it. For more on building a balanced diet, see our guide on what to feed your hens for high-quality eggs.
Soluble grit vs insoluble grit: an important difference
Before we make our homemade grit, it is worth clearing up a common source of confusion, because the word “grit” is used for two completely different things:
- Soluble grit (calcium grit) – crushed eggshell, oyster shell or limestone. This dissolves in the hen's system and provides the calcium she needs to make strong eggshells. This is what we are making in this article.
- Insoluble grit (flint grit) – small, hard pieces of flint or granite. This does not dissolve. It sits in the gizzard and helps the hen grind down and digest her food, since chickens have no teeth.
The key takeaway: homemade eggshell grit is a calcium supplement, not a digestive grit. It is brilliant for eggshell quality, but it does not replace the hard, insoluble flint grit your hens also need to grind their food – especially if they eat whole grains or forage in the garden. Most keepers offer both. For a fuller explanation, read our guide to the nitty-gritty of mixed hen grit.
How to make homemade grit from eggshells (step by step)
Turning eggshells into calcium grit for your chickens takes just a few minutes of hands-on time. Here is how to do it safely.
Step 1: Save and rinse your eggshells
Every time you cook with eggs, keep the shells instead of throwing them away. Give them a quick rinse under the tap to remove any leftover egg white or yolk, then leave them out to air dry. Collecting shells in a tub on the worktop for a week or two means you can prepare a decent batch in one go.
Step 2: Dry or bake the eggshells
Once your shells are clean, you want them fully dry and brittle. Air drying is enough for many keepers, but baking is a tidy option that also makes the shells easier to crush. Pop the shells on a baking tray, spread them out evenly, and bake at around 180°C (fan 160°C) for roughly 10 minutes until dry and crisp. Keep an eye on them so they do not scorch.
Step 3: Crush so they are not recognisable as eggs
This step matters. Crush the dried shells well – with a rolling pin, in a pestle and mortar, or briefly in a food processor – until they are broken into small, irregular pieces and no longer look like eggs. Why? Offering shells that still resemble a whole egg can, in theory, encourage hens to start pecking at and eating their own freshly laid eggs. Crushing them into unrecognisable fragments avoids any chance of teaching that habit.
Step 4: Store in an airtight container
Tip your crushed eggshell into a clean jar or tub with a lid and keep it somewhere dry. Stored properly, homemade eggshell grit will keep for months, so you always have a supply ready to top up.
How to feed eggshells to chickens (and how much)
The simplest and safest way to offer homemade grit is free-choice: put the crushed eggshell in a small separate dish or feeder, alongside – but not mixed into – their normal food and water. Hens are very good at self-regulating their calcium intake, so a laying hen will help herself to what she needs and leave the rest.
Offering it separately (rather than stirring it into their feed) is better because not every bird in your flock needs the same amount – a hen in full lay needs far more calcium than a youngster or a hen who has stopped laying. Keep the dish topped up, check it now and then, and let your hens do the rest. For the bigger picture on feed types and supplements, our overview of the different types of feed for your chickens is a handy companion read.
Benefits of homemade eggshell grit
- Cost-effective: you are repurposing something you would otherwise throw away, saving on shop-bought calcium grit.
- Natural and nutritious: eggshell is an excellent, readily available source of calcium for your laying hens.
- Less waste: repurposing your shells cuts down kitchen waste and fits neatly into a more sustainable way of keeping chickens.
If you ever notice persistently soft, thin or unusual eggshells despite offering plenty of calcium, it is worth speaking to your vet or a qualified poultry specialist, as this can occasionally point to a health issue rather than a simple diet gap.
Frequently asked questions
Can chickens eat eggshells raw, or do they need cooking?
Chickens can eat clean, dried raw eggshells, but rinsing and drying (or briefly baking) them is sensible to keep them hygienic and brittle. Whichever you choose, always crush the shells well so they are no longer recognisable as eggs before offering them.
Will feeding eggshells make my hens eat their own eggs?
Not if you crush them properly. The risk only arises if hens are given whole or large pieces of shell that still look like an egg. Crushing the shells into small, unrecognisable fragments removes that risk.
Do eggshells replace normal grit for chickens?
No. Eggshell is a soluble calcium grit for making strong eggshells. Your hens still need insoluble flint grit to grind and digest their food, so offer both. See our guide to mixed hen grit for more.
How much eggshell grit should I give my chickens?
There is no need to measure it out – simply offer crushed eggshell free-choice in a separate dish and let your hens take what they need. They are good at self-regulating their calcium intake.
Happy, healthy hens start with the right setup
Good calcium is just one part of keeping a thriving flock. A dry, secure, easy-clean home matters too – which is exactly what a Nestera chicken coop is built for. Made from durable recycled plastic with a 25-year guarantee, our coops are maintenance-free and naturally resistant to red mite, so you can spend less time scrubbing and more time enjoying your hens (and their lovely strong-shelled eggs).
