Incubation Calendar: Candling, Lockdown and Hatch Dates
Incubation runs on a schedule, and the two dates people miss — lockdown and the day to stop turning — are the ones that decide the hatch. Set the day the eggs went in.
The two dates that decide the hatch
Most of an incubation run is waiting. The parts that actually need a date in the calendar are the candling checks, and — far more importantly — lockdown: the day you raise the humidity, stop turning the eggs, and stop opening the incubator.
Pick the species and set the date the eggs went in. Everything below is calculated from the schedule table further down the page, which lists the day counts in full.
| Example | First candling | Second candling | Lockdown — stop turning | Hatch day | Give up after |
|---|---|---|---|---|---|
| Chicken eggs set 1 April | 2026-04-08 | 2026-04-15 | 2026-04-19 | 2026-04-22 | 2026-04-25 |
| Duck eggs set 1 April | 2026-04-08 | 2026-04-15 | 2026-04-26 | 2026-04-29 | 2026-05-02 |
| Muscovy set 1 April | 2026-04-08 | 2026-04-19 | 2026-05-02 | 2026-05-06 | 2026-05-09 |
| Coturnix quail set 1 April | 2026-04-06 | 2026-04-11 | 2026-04-15 | 2026-04-18 | 2026-04-21 |
| Goose eggs set 1 April | 2026-04-08 | 2026-04-16 | 2026-04-28 | 2026-05-01 | 2026-05-04 |
| Species | Hatch (days) | First candling (days) | Second candling (days) | Lockdown / stop turning (days) |
|---|---|---|---|---|
| chicken | 21 | 7 | 14 | 18 |
| duck | 28 | 7 | 14 | 25 |
| muscovy | 35 | 7 | 18 | 31 |
| quail_coturnix | 17 | 5 | 10 | 14 |
| quail_bobwhite | 23 | 7 | 14 | 20 |
| turkey | 28 | 7 | 14 | 25 |
| goose | 30 | 7 | 15 | 27 |
| guinea | 27 | 7 | 14 | 24 |
Day counts follow standard hatchery and extension incubation guidance. Several are genuinely a range rather than a fixed number — geese run 28 to 35 days depending on breed, and Muscovy are the well-known outlier among ducks at 35. Lockdown day is listed separately rather than derived as "three days before hatch" because the interval is not the same for every species, and because whether chicken lockdown falls on day 18 or 19 is a real disagreement between sources; day 18 is used here.
Assumptions and limits
- Day counts assume a correctly calibrated incubator holding temperature. Eggs running cool hatch late; eggs running warm hatch early and more often with defects.
- The day eggs go in is day 0, so a chicken hatching "on day 21" hatches 21 days later. Hatcheries and books differ on whether they count from 0 or 1 — a one-day discrepancy against another source is almost always this.
- Species where the range is wide are listed at the common value: geese vary from 28 to 35 days by breed, so check yours if it is not a common one.
- Candling dates are guidance, not deadlines. Candling less is better than candling often; every opening costs heat and humidity.
- All dates are calendar dates with no time zone applied — the incubator does not care which side of midnight you set the eggs.
What lockdown actually does
In the last few days before hatching, the chick moves into position, breaks into the air cell and starts breathing air before it works on the shell. That process needs higher humidity, because the membrane surrounding the chick dries out fast in dry air, and a dried membrane traps a chick that was otherwise perfectly healthy.
This is why lockdown is the single point in the whole run where discipline matters most. Opening the incubator to check on a pipping egg drops the humidity in seconds, and the membrane starts drying against a chick that cannot turn to escape it. The urge to help is strongest at exactly the moment when helping does the most harm.
Why candling early is worth the trouble
The first candling separates eggs that were never fertile from eggs that are developing. This is not about tidiness. An infertile egg sitting at incubation temperature for three weeks is a bacterial culture, and if one bursts late in the run it can contaminate the whole batch.
The second candling catches early deaths for the same reason. After that, leave them alone — every check costs heat and humidity, and by then there is nothing left to act on.
When the dates slip
An incubator running half a degree cool will hatch a day or two late; running warm, it hatches early, and early hatches carry more leg and navel problems. If a whole batch is running consistently off schedule, the incubator calibration is the thing to check, not the eggs.
Stragglers are normal. A hatch spread over 24 to 36 hours is ordinary; the "give up after" date is three days past due, and past that point unhatched eggs are not going to hatch.