Egg Incubation Calculator
Timing is everything in egg incubation — a single day off on lockdown can ruin your hatch. Select your bird species and set date to get precise hatch day, lockdown date, candling schedule, temperature, humidity settings, and expected yield. Supports chicken, duck, turkey, quail, goose, and more.
Incubation Schedule Calculator
Incubation Periods by Species
| Species | Days | Temp (°F) | Humidity | Lockdown Day | Lockdown Humidity |
|---|---|---|---|---|---|
| Chicken | 21 | 99.5°F | 45% | Day 18 | 65% |
| Duck (Mallard/Pekin) | 28 | 99.5°F | 55% | Day 25 | 75% |
| Muscovy Duck | 35 | 99.5°F | 55% | Day 32 | 75% |
| Turkey | 28 | 99.5°F | 55% | Day 25 | 70% |
| Goose | 30 | 99.5°F | 55% | Day 27 | 75% |
| Quail (Coturnix) | 17 | 99.75°F | 45% | Day 14 | 65% |
| Guinea Fowl | 28 | 99.5°F | 50% | Day 25 | 70% |
| Pheasant | 24 | 99.5°F | 50% | Day 21 | 65% |
Step-by-Step Incubation Process
Successful egg incubation requires maintaining precise environmental conditions throughout the development period. The process breaks into three distinct phases: setting (placing eggs and stabilizing conditions), development (daily turning and monitoring), and lockdown (final preparation for hatching).
Before setting eggs, run your incubator empty for 24-48 hours to verify temperature stability. Temperature fluctuations of even 0.5°F can impact development. Use a calibrated thermometer — the incubator's built-in gauge may be inaccurate.
Hatch Rate Formula
Expected Hatchlings = Eggs Set × Fertility Rate × 0.80
The 0.80 factor accounts for the typical 80% hatch rate from fertile eggs under good incubation conditions. Experienced incubators with calibrated equipment often achieve 85-95%. First-time hatchers may see 60-70%. Track your rates to identify improvements needed.
Real-World Example
Setting 24 chicken eggs on March 1st with 90% estimated fertility:
- First candle: March 8 (day 7) — remove clear/infertile eggs
- Second candle: March 15 (day 14) — verify development
- Lockdown: March 19 (day 18) — stop turning, raise humidity to 65%
- Expected hatch: March 22 (day 21)
- Fertile eggs: 24 × 0.90 = ~22 fertile
- Expected hatchlings: 22 × 0.80 = ~17-18 chicks
Common Incubation Mistakes
- Opening the incubator during lockdown. Every opening drops humidity dramatically and can shrink-wrap chicks in their membranes.
- Helping chicks out of the shell. Premature assisted hatching causes unabsorbed yolk sac, bleeding, and death. Wait 24+ hours after external pip before considering help.
- Setting dirty or cracked eggs. Bacteria enter through cracks and pores, causing "exploding" eggs that contaminate the entire batch.
- Not calibrating the thermometer. A thermometer reading 1°F high means the incubator is actually 1°F too hot — devastating over 21 days.
- Forgetting to turn eggs. Without turning, the embryo sticks to the shell membrane and dies. Auto-turners are a worthwhile investment.
Planning a backyard flock? Calculate your coop needs with the chicken coop calculator. Manage compost from your flock with the compost ratio calculator, or plan your garden alongside with the seed starting calculator.
Frequently Asked Questions
What temperature should I incubate chicken eggs at?
Chicken eggs require a consistent 99.5°F (37.5°C) in a forced-air incubator. In a still-air incubator (no fan), set temperature to 101-102°F measured at the top of the eggs, since heat stratifies without air circulation. Temperature accuracy is critical — even 1°F too high can cause birth defects or death, while 1°F too low delays development and reduces hatch rates.
How many times should I turn eggs during incubation?
Turn eggs a minimum of 3 times per day (odd number so the egg spends alternating nights on different sides). More frequent turning (5-7 times) improves hatch rates. Mark eggs with an "X" on one side and "O" on the other to track rotation. Stop turning 3 days before the expected hatch date (day 18 for chickens) — this is "lockdown" when the chick positions itself for hatching.
What is lockdown in egg incubation?
Lockdown is the final 3 days before hatch day when you stop turning eggs, increase humidity (to 65-75%), and avoid opening the incubator. During lockdown, the embryo absorbs the remaining yolk sac, positions itself head-toward-the-air-cell, and internally pips (breaks into the air cell for first breathing). Opening the incubator during lockdown drops humidity rapidly, which can cause membranes to dry and shrink-wrap the chick.
What humidity level is best for incubating eggs?
For chicken eggs: 40-50% relative humidity during days 1-18, then 60-70% during lockdown (days 18-21). Proper humidity controls moisture loss through the shell — eggs should lose approximately 13% of their weight by lockdown day. Too much humidity causes the air cell to remain too small, drowning the chick. Too little humidity makes the air cell too large and membranes too tough for the chick to break through.
How do I candle eggs during incubation?
Candling means shining a bright light through the shell in a dark room to see development. First candle at day 7-10 to check for veins (fertile) vs clear eggs (infertile) or blood rings (early death). Remove infertile and dead eggs to prevent bacteria. Candle again at day 14-18 to confirm growth. The air cell should be about 1/3 of the egg at lockdown. Use a bright LED flashlight and work quickly — eggs cool fast outside the incubator.
Why did my eggs not hatch?
Common causes include: infertile eggs (rooster not mating successfully), temperature too high or low, incorrect humidity, eggs not turned enough, old eggs before incubation (over 10 days reduces viability), bacterial contamination from dirty eggs, power outages, and genetic defects. Keep a log of temperature and humidity readings. A 70-80% hatch rate from fertile eggs is considered good for home incubation.
How long can eggs be stored before incubation?
Store eggs pointy-end down at 55-65°F (12-18°C) and 75% humidity. Eggs stored for 1-7 days have the best hatch rates (85-90%). At 10 days, viability drops to ~70%. At 14 days, expect ~50%. After 21 days of storage, very few will develop. Tilt stored eggs 45° twice daily to prevent the yolk from sticking to the shell membrane. Never refrigerate eggs you plan to incubate.
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