How to Select and Store Hatching Eggs: The Guide to a Higher Hatch Rate

Hatching success begins long before you press the incubator's start button. The first factor that determines your hatch rate is the quality of the eggs you set: even the best incubator cannot hatch chicks from poorly selected or badly stored eggs. This guide explains step by step how to select hatching eggs, how long and under what conditions to store them, and how to handle shipped eggs.

For the incubation process itself, see our 21-day chicken incubation guide; this article covers "day zero" — everything before the eggs go into the machine.

Hatch Rate Starts with the Breeding Flock

Fertile, strong eggs come from a healthy breeding flock:

• Rooster ratio: One rooster per 8-10 hens is ideal. With no rooster, the eggs are infertile and none will hatch.
• Age: The best hatching eggs come from hens between 1 and 3 years old. Eggs from very young pullets that have just started laying are small and hatch poorly.
• Nutrition: The breeding flock should be fed a breeder ration rich in vitamins and minerals. Nutrient deficiency is an invisible cause of embryo death during development.
• Health: Never set eggs from sick or parasite-ridden birds.

Which Eggs Are Suitable for Incubation?

Not every collected egg is a hatching egg. Check for:

• Shape: A normal, oval egg shape. Cull eggs that are too round, too pointed or deformed.
• Size: Choose eggs of average size for the breed. Very large eggs are often double-yolked and won't hatch; very small eggs produce weak chicks.
• Shell: A sound, smooth shell of normal thickness. Cull thin, calcium-deposited, wrinkled or visibly porous shells.
• Crack check: Hairline cracks may be invisible to the eye. Candle the eggs against a light source to find hairline cracks; a cracked egg rots in the incubator and contaminates the others.
• Cleanliness: Choose clean or only lightly soiled eggs. Heavily soiled eggs (droppings, mud) should not go into the incubator.

Why You Must Not Wash Hatching Eggs

The eggshell carries a natural, invisible protective layer called the cuticle (bloom). It seals the shell's pores against microbes. Washing the egg with water destroys the cuticle and lets bacteria in through the pores — washed eggs are far more likely to rot during incubation.

Wipe a lightly soiled egg gently with a dry cloth or very fine sandpaper. Do not wash with water or wipe with a wet cloth.

How Long Can Hatching Eggs Be Stored?

The fresher the egg, the higher the hatch rate. The general rule: set eggs within 7 days.

Storage time	Expected effect
1-3 days	Highest hatch rate
4-7 days	Normal — negligible loss
8-10 days	Noticeable decline begins (about 1% per day)
11-14 days	Serious decline; chicks may hatch late and weak
Over 14 days	Not recommended

If your eggs are collected a few at a time, plan to incubate in 7-day batches rather than accumulating them all.

The Right Storage Conditions

• Temperature: The ideal storage temperature is 12-16 °C (54-61 °F). A cool pantry or basement works. Do not refrigerate — below 10 °C damages the embryo. Don't keep them above room temperature (20 °C+) either; the embryo starts developing irregularly.
• Humidity: Around 70-80% humidity slows the egg's water loss. In a very dry room, the air cell grows too fast.
• Position: Store the eggs in a tray pointed end down, blunt end (air cell) up.
• Tilting: If storing longer than 7 days, prop up one end of the tray and switch sides once or twice a day (left side high one day, right side the next) so the yolk doesn't stick to the shell.
• Vibration and sun: Keep away from direct sunlight and vibration.

Shipped Eggs

Eggs bought remotely and shipped get shaken in transit; the most common problem is a detached or displaced air cell. For shipped eggs:

1. Unpack and place the eggs in a tray pointed end down.
2. Let them rest at room conditions for at least 12-24 hours before setting. This lets the air cell settle back into place.
3. After resting, candle the eggs: separate those with a rolling or displaced air cell. Incubating these upright (pointed end down) instead of on their side, without turning for the first 3-5 days, improves their chances.
4. A lower-than-normal hatch rate for shipped eggs (around 50%) is expected — don't be discouraged.

Before Setting the Eggs

• Bring to room temperature: Don't move eggs from cool storage straight into a 37.8 °C incubator; condensation ("sweating") forms on the shell and carries microbes in through the pores. Bring the eggs to room temperature 4-8 hours before setting.
• Pre-run the incubator: While the eggs rest, run the incubator for at least 24 hours and verify temperature and humidity with a separate thermometer-hygrometer.
• Mark them: If turning by hand, pencil an X on one side of each egg and an O on the other.

The Most Common Mistakes

• Washing eggs with water (destroys the cuticle).
• Storing in the refrigerator (kills or weakens the embryo).
• Accumulating eggs for 2-3 weeks and setting them all at once (the old ones won't hatch).
• Setting shipped eggs immediately without a rest period.
• Moving cold eggs straight into the warm incubator (sweating).
• Picking extra-large double-yolk eggs as "better fed" (they don't hatch).

Once your eggs are set, you can track the process day by day with the KuluçkaTakip app: pick the species, enter the start date, and let the app remind you of turning, candling and hatch days. If your hatch turns out low, find the causes in our troubleshooting guide.