Egg Incubation Calculator

Hatch date, lockdown, and candling dates for poultry eggs.

What it does

Incubation adds a fixed species period to the set date: 21 days for chickens, 28 for ducks and turkeys, 30 for geese. Two checkpoints ride along: candling around day 7 to 10 and lockdown three days before hatch.

The tool above takes the species with the set date. It returns the hatch date with lockdown and candling dates beside them.

The default chicken set March 1 2026 hatches March 22 with lockdown March 19 and candling March 8 to 11. Ducks set the same day hatch March 29 with lockdown March 26.

Periods follow University of Minnesota Extension hatching guidance with Mississippi State Extension tables matching them. Both run forced air near 99.5 F with humidity rising for the final three days.

How to use

1. Pick the species first.
2. Enter the day eggs go into the incubator.
3. Read the hatch date for the calendar mark.
4. Prepare lockdown three days before: no turning.
5. Candle in the shown window and clear the clears.

Formula

21/28/30

Species incubation days.

minus 3

Lockdown offset before hatch.

7-10

Candling window for clears.

All dates compute in UTC so zones never shift a day. Cool running hatches late and warm runs early by about a day either way.

Worked example

Reference table

Limits

• Averages; temperature swings shift a day either way.
• Single species per batch; mixed hatches conflict.
• Shipped eggs hatch worse than local fertile eggs.
• Old eggs past 10 days lose hatchability fast.

Common mistakes

• Counting set day as day one (lands a day early).
• Turning during lockdown and shrink wrapping chicks.
• Chasing humidity numbers while ignoring weight loss.
• Opening the lid repeatedly during hatch.
• Mixing species on one schedule.

Try it yourself

Quick checks. Answers sit tucked under each question.

Questions

Sources

• UMN Extension: hatching
• MSU Extension

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