Chicken eggs take about 21 days to hatch — 21 days to 21 days and 6 hours in a well-run incubator, according to University of Missouri Extension. Set your eggs, add 21 days, and you have your hatch date. The calculator above does this for you and also marks the two dates that matter most along the way: when to candle (day 7–10) and when to stop turning and go into “lockdown” (day 18).
The number the calculator uses
The tool adds each species’ incubation period to the date you set the eggs. For chickens that period is 21 days. Hatch timing shifts a little with egg size, breed, egg storage before setting, and how accurately your incubator holds temperature — so treat the result as a target, not a guarantee. It’s normal for some chicks to pip a day early or a day or two late; Purina suggests giving stragglers until about day 23 before giving up on them.
Getting to a good hatch comes down to four things every extension service repeats: temperature, humidity, ventilation, and turning. Of these, Virginia State University’s poultry specialist notes that temperature is the most critical, while humidity is the one most often mishandled.
Temperature. Run a forced-air incubator (one with a fan) at 99.5–100°F (37.5–37.8°C). A still-air incubator should read a bit higher — about 100.5–102°F measured at the top of the eggs — because heat layers without a fan, per Mississippi State University Extension. Cross-check the built-in gauge with a second thermometer; sustained temperatures above 103°F kill embryos.
Humidity. Hold roughly 45–55% relative humidity for days 1–18, then raise it to 65–75% for the final three days so chicks don’t dry out and stick to the shell. Extension figures vary a little by tradition — some cite 50–60% for the early phase — but the real target is weight loss: eggs should shed about 11–14% of their starting weight by day 18, which is MU Extension’s more precise measure of correct humidity.
Turning. Turn eggs an odd number of times a day — at least 3 to 5, or up to 4–6 by MSU’s guidance — until day 18, then stop. An automatic turner makes this far easier.
How long do chicken eggs take to hatch?
On average, 21 days. In practice most chicks hatch between day 20 and day 23. Cooler-running incubators tend to hatch late; warmer ones hatch early — and in both cases the total number of chicks usually drops, which is why steady temperature matters more than hitting an exact hatch day. Other poultry run longer: this is a big reason you generally shouldn’t set very different species on the same schedule. The reference table below shows the incubation period and lockdown day for the common backyard species.
Incubation period chart by species
| Species | Incubation period (days) | Stop turning (lockdown) | Forced-air temp |
|---|---|---|---|
| Chicken | 21 | Day 18 | 99.5–100°F |
| Turkey | 28 | Day 25 | 99°F |
| Duck (most breeds) | 28 | Day 25 | 99.5–100°F |
| Muscovy duck | 35–37 | Day 31 | 99.5–100°F |
| Goose | 28–34 | Day 25 | 99°F |
| Guinea fowl | 28 | Day 25 | 99.5–100°F |
| Pheasant | 23–28 | Day 21 | 99.5–100°F |
| Peafowl | 28–30 | Day 25 | 99°F |
| Bobwhite quail | 23–24 | Day 20 | 99.5–100°F |
| Coturnix quail | 17 | Day 15 | 99.5–100°F |
| Pigeon | 17 | Day 15 | 99.5–100°F |
Species periods and lockdown days from Mississippi State University Extension. Temperatures are forced-air targets; add 2–3°F for still-air incubators.
How to use the chicken egg incubation calculator
- Enter the date you set the eggs in the incubator (it defaults to today).
- Choose the species — chicken is selected by default.
- Read your estimated hatch date, the hatch window, and the day-7–10 candling and day-18 lockdown dates.
- Open the temperature & humidity chart for the targets at each stage, and use Print / save to keep a copy by the incubator.
Chicken Egg Incubation Calculator
Temperature, humidity & incubation-period chart
| Stage | Days | Temp | Humidity (RH) | Turning |
|---|---|---|---|---|
| Incubation | 1–18 | 99.5–100°F (37.5–37.8°C) | 45–55% | 3–5× daily |
| Lockdown / hatch | 19–21 | 99.5°F (still-air 100.5–102°F) | 65–75% | Stop turning |
| Species | Days | Stop turning | Temp |
|---|
How it works: Chicken eggs hatch in about 21 days. The calculator adds each species' incubation period to your set date, then flags the day-7–10 candling check and the day-18 "lockdown" (stop turning, raise humidity). Some chicks pip a day early or late.
Disclaimer: Estimates for planning only — not veterinary advice. Actual hatch timing varies with egg size, breed, storage, and incubator accuracy. Keep daily records and follow your incubator manufacturer's guidance.
Sources:
Frequently asked questions
What temperature should I incubate chicken eggs at?
99.5–100°F (37.5–37.8°C) in a forced-air incubator, or about 100.5–102°F at the top of the eggs in a still-air incubator, per Mississippi State Extension. Keep it steady — swings do more harm than a stable reading that’s a few tenths off.
What humidity do chicken eggs need?
About 45–55% relative humidity for days 1–18, then 65–75% for the last three days to help chicks hatch, based on University of Illinois and Penn State guidance. If you can weigh eggs, aim for roughly 11–14% weight loss by day 18.
When should I candle chicken eggs?
Around day 7 to 10, when blood vessels become visible in a live embryo; candle a few at a time and keep each egg out of the incubator under 5–10 minutes. Many keepers candle again just before lockdown to pull any clear (infertile) eggs.
What is “lockdown” and when does it start?
Lockdown is the last three days — day 18 for chickens. Stop turning, raise humidity to 65–75%, open the vents a little more, and keep the lid closed so chicks can hatch in a stable, humid environment.
How long can chicken eggs be stored before incubating?
Store fertile eggs at about 55–60°F with the small end down and set them within 7 days for the best hatch; storing longer steadily lowers hatchability, per MU Extension.
Can you incubate chicken and goose eggs together?
It’s generally not recommended. Geese incubate for about 28–34 days versus 21 for chickens, and waterfowl need higher humidity, so the two won’t share a lockdown date or moisture level. If you must combine them, the different hatch times mean you’ll be opening the incubator during another species’ lockdown — which hurts the hatch. Running them in separate machines (or at least on staggered set dates) is far more reliable.
Sources
- Mississippi State University Extension — Important Incubation Factors
- University of Missouri Extension — Incubation of Poultry (G8353)
- University of Illinois Extension — Incubation & Embryology Q&A
- Penn State Extension — Science of Incubation
- Virginia State University (via The Poultry Site) — Incubating Eggs
Reviewed for accuracy against Mississippi State, Missouri, Illinois, and Penn State Extension guidance. Last updated: July 15, 2026.
Related BarnCalc tools: visit the chicken hub, or try the coop size calculator, chicken feed calculator, and egg production calculator.
Related BarnCalc tools: visit the poultry hub, or try:
- Chicken Feed Calculator
- Duck Egg Incubation Calculator
- Goose Egg Incubation Calculator
- Quail Egg Incubation