Guinea Fowl Incubation Calculator (100% FREE)

Set a hatch date and this calculator builds your entire incubation schedule around it — lockdown timing, candling dates, the right temperature and humidity, and a day-by-day status update so you always know exactly where you are in the process.

How This Calculator Works

Enter your set date and a few details about your setup, and the calculator tracks incubation from day 1 through hatch — updating automatically based on today’s date.

• Date eggs go in — everything else is calculated from this. The tool defaults to today, but you can set any date, past or future.
• Incubation method — forced-air incubator, still-air incubator, a broody guinea hen, or a broody chicken hen. Each gets different guidance: incubators show temperature, humidity, and turning schedule; broody hens show nest care and disturbance advice instead, since you’re not managing climate directly.
• Number of eggs — used for the egg count confirmation and, for broody-hen methods, clutch-size guidance.
• Turning setup — automatic turner or manual turning for incubators. If you select a broody hen as your method, this locks to “handled by the hen,” since she manages her own turning.
• Planning hatch day — day 27 or day 28. Guinea eggs typically hatch between day 26 and day 28, with 28 the standard planning figure most hatchery guides use. This choice only shifts your headline “expected hatch” date — lockdown and candling stay anchored to the fixed schedule either way.
• Egg source — fresh from your own flock, or shipped/from elsewhere. Shipped eggs get a reminder to rest 24 hours at room temperature before setting, which helps air cells settle after transit.

What You’ll Get

• Expected hatch date, with the typical day 26–28 hatch window shown alongside it
• Lockdown date — the day to stop turning and raise humidity
• Days remaining or days to lockdown, depending on where you are in the schedule
• Current incubation day, once your set date has passed
• Temperature and humidity targets — different before and after lockdown, and different again for still-air versus forced-air incubators
• Candling schedule for day 7 and day 14, with what to look for at each check
• Turning frequency appropriate to your setup
• Clutch-size guidance for broody-hen methods, flagging if your egg count is within the typical comfortable range or likely to lower hatch rates
• A live status update that changes as the days pass — from “not started yet,” through active incubation, into lockdown, and through the hatch window itself

Why Forced-Air and Still-Air Incubators Get Different Numbers

If you’re using a still-air incubator (no internal fan), you’ll notice the temperature target is a few degrees higher than a forced-air unit — 100.5–101.5°F, measured at the top of the eggs, compared to a steady 99.5°F for forced-air. That’s not a typo. Still-air units stratify: warmer air rises and pools near the top, so the temperature right at egg level runs cooler than the incubator’s overall reading unless you’re measuring in the right spot. Forced-air incubators circulate air with a fan, keeping the whole chamber even — which is part of why they’re the easier setup to keep stable.

Why Guinea Eggs Need Different Humidity Than Chicken Eggs

Guinea fowl eggs have unusually thick shells and lose moisture more slowly than chicken eggs. That’s why humidity is kept lower in the first 25 days — 45–50%, rather than the higher range often used for chicken eggs — before jumping to 65–70% during lockdown. Too much humidity early on is one of the more common, preventable causes of a failed hatch, since it stops the egg from losing the moisture it needs to develop a proper air cell before hatching.

Choosing Between an Incubator and a Broody Hen

Guinea hens themselves are notoriously inconsistent mothers — many will abandon the nest the moment the first keets hatch, leaving any late eggs to chill before they’ve had a chance. A broody chicken hen is widely considered the better natural option for guinea eggs: steadier brooding behavior, and she can typically cover a noticeably larger clutch (20–28 eggs) than a guinea hen managing her own (12–15 eggs) — though there’s no strict cutoff where a hen “suddenly” can’t manage more eggs; hatch rates just tend to decline gradually as a clutch grows past what she can keep evenly warm. If you don’t have a broody hen available at all, an incubator gives you full control over the variables that matter most. Our complete guide to hatching guinea fowl eggs walks through the trade-offs in more depth if you’re still deciding which route fits your setup.

Understanding Your Hatch Window

Day 28 is the standard planning figure, but it’s genuinely a window, not a fixed appointment — most hatches happen between day 26 and day 28, and occasional stragglers can go as late as day 29 to 31. That’s why the calculator’s status updates get more cautious rather than more certain as you move past the expected date: a hatch that hasn’t happened by day 29 or 30 isn’t necessarily a lost cause, but it’s worth candling to check rather than assuming the worst or the best. For the full day-by-day breakdown of what’s happening inside the egg at each stage, see our incubation timeline guide.

Getting the Most Out of This Calculator

• Set your date accurately. Every other number — lockdown, candling, hatch window — is calculated from this one input.
• Don’t open the incubator during lockdown unless you’re candling. Humidity loss in the final days affects every remaining egg, not just the one you’re checking on.
• Candle on schedule, not just when curious. Day 7 (looking for a dark spot and blood vessels) and day 14 (a large dark mass, hard to see through) are the two checkpoints most likely to give you useful information without unnecessary handling.
• If you’re choosing eggs to set, freshness matters — eggs less than 7 to 10 days old generally hatch better, and if you’re working with nesting box collection from your own flock versus eggs sourced elsewhere, that timing is worth tracking closely.

Not sure yet whether you want to start from eggs, keets, or adult birds at all? Our guide on buying your first guinea fowl breaks down the trade-offs before you get to the incubator stage. And if the question on your mind is less “how do I hatch these” and more “how many eggs will my flock even produce,” that’s covered separately in our guide to guinea fowl egg production and the Egg Production Calculator linked below.

Frequently Asked Questions

How long does it take for guinea fowl eggs to hatch?
Guinea eggs typically hatch between day 26 and day 28 of incubation, with day 28 commonly used as the standard planning figure. Occasional hatches as late as day 29 to 31 do happen, so it’s worth treating the expected date as a window rather than a fixed deadline.

What temperature should I set my incubator to?
99.5°F (37.5°C) for a forced-air incubator. For a still-air incubator, run it warmer — 100.5–101.5°F — and measure at the top of the eggs, since still-air units run cooler at egg level than their overall reading suggests.

When should I stop turning the eggs?
Turn at least three times a day (ideally every 6–8 hours) through day 25, then stop entirely once lockdown begins. Turning during lockdown can disrupt chicks that are already repositioning to hatch.

Can a chicken hen hatch guinea fowl eggs?
Yes, and many keepers prefer it — a broody chicken hen tends to be a steadier, more reliable sitter than a guinea hen herself, and can typically cover a larger clutch of guinea eggs than a guinea hen managing her own nest.

How many eggs can one broody hen cover?
For a guinea hen, 12–15 eggs is the typical comfortable range. For a large broody chicken hen, that extends to roughly 20–28 eggs. Beyond those ranges, hatch rates tend to decline gradually rather than dropping off at one exact number — the calculator flags this based on the eggs you enter.

What if my eggs haven’t hatched by day 28?
Don’t panic right away — hatches as late as day 29 to 31 aren’t unheard of. If nothing has happened by around day 30–31, remaining eggs become increasingly unlikely to be viable, and candling can help you decide whether to keep waiting.