How to Use a Chicken Incubator | 21-Day Hatch Guide

Here is how to set up and run an incubator without the costly mistakes.

Setting Up Your Incubator for Success

Start one week before eggs arrive. Clean the incubator with a mild bleach solution—⅓ cup bleach per gallon of water—keeping it off heating elements and electronics. Let it dry completely.

Place it in a draft-free room at 68–77°F ambient temperature, away from sunlight, radiators, or heat vents. Run the empty incubator for 2–3 hours (24 hours is better) to stabilize, then verify readings against a separate thermometer and hygrometer. Built-in sensors on budget units can be off by 2–3 degrees.

Fill the water troughs and let humidity settle. Use fresh, clean, uncracked eggs from a reputable source. If eggs were shipped, rest them 24 hours at room temperature before loading. Mark each egg with an X on one side so you can track turning. Place eggs on their side, large end slightly elevated, about 2 centimeters from the tray edge.

If you are shopping for your first incubator, a roundup of the best incubators for beginners can help you choose one with reliable temperature control and easy humidity management.

Using a Chicken Incubator: Temperature and Humidity Rules

The incubation period splits into two phases with different settings. The table below covers the exact numbers for each phase.

Days 1–17. Keep the temperature at 100.5°F if your incubator allows fine control; anything between 99 and 102 works. Humidity stays at 50–55%. Turn eggs an odd number of times each day—three to five rotations—by gently rolling each egg 180 degrees. The odd number ensures the egg never rests on the same side two nights in a row. Candle around day 7 or 10 to check development. A fertile egg shows a dark spot with radiating blood vessels; clear eggs or those with a visible blood ring are infertile and should be removed.

Per UNL Extension’s incubation guidelines, even a 1-degree temperature swing can cut hatch rates noticeably. Check your thermometer daily and recalibrate if needed. Keep vents open throughout—restricted airflow is a common hidden cause of late-term deaths.

What Happens During Lockdown (Days 18–21)?

Day 18 is the most critical transition. Stop turning eggs immediately—any movement after this point disorients the chick and prevents proper hatching position. Increase humidity to 65–70% by adding water to the troughs or a wet sponge. Lower temperature slightly to 98.8–99°F.

Close the lid and leave it closed until the hatch is complete. Opening releases heat and humidity at the worst possible moment. Chicks pip the shell, then rest—sometimes 12 hours or more. Do not help them out. Once a chick is dry and fluffy, move it to a brooder. Keep the incubator running for any late hatchers.

FAQs

How often should I turn eggs in an incubator?

Turn eggs three to five times each day during days 1–17. Using an odd number prevents the egg from sitting on the same side for two consecutive nights. Automatic turners make this easier, but manual turning works if you stick to the schedule.

Can I open the incubator during lockdown?

No. Opening the lid after day 18 releases the heat and humidity chicks depend on to hatch. The only exception is a single quick check if you suspect all eggs are dead, which is rare with correct incubation.

Why did my hatch rate turn out low?

The most common causes are temperature drift, early-stage humidity above 60%, or continuing to turn eggs after day 18. Poor ventilation or eggs from an unhealthy flock also reduce hatch rates significantly.