Egg Boiling Time Calculator by Altitude
Perfect eggs, every time ⏱️🥚
Get precise boiling times based on your altitude, egg size, and desired doneness. Science-backed calculations for perfect results.
Select the size of your eggs
Drop eggs into already boiling water
1-24 eggs. Batches over 4 need extra time.
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A boiled egg is a small heat-transfer problem, and a time that works in one kitchen won't work at every altitude. The form above turns the inputs into a time for your own timer. The guides are the longer versions. The recipes are what to cook after the eggs chill.
Your altitude sets the water temperature
Water boils when its vapor pressure equals the air pressing on it. Climb, and that air presses less, so the match happens cooler. USDA FSIS describes the drop as just under 1°F for each 500 feet. A pot at a few thousand feet is not the same heat as a pot at sea level, even when both look like a full boil. The science of boiling eggs walks through the pressure and the protein temperatures.
Egg size changes how far the heat has to travel
Carton size is a weight class, not a guess about shape. A heavier egg puts more white between the shell and the yolk, so heat has farther to travel and more mass to warm before the center can set. Pick your egg size; the calculator adjusts the time. Match the control to the carton. If the carton is mixed, time the batch for the largest egg.
Fridge-cold or room-temperature start
An egg from the refrigerator is near 4°C (39°F). One that has been in the kitchen is nearer 20°C (68°F). The colder egg has more degrees to climb, so it needs slightly more time in the same water. Set the starting-temperature control to the egg you have. Parking a cold carton on the counter is not part of the calculation, and a refrigerated egg should stay cold until you cook it.
Pick your doneness
Doneness is the center you stop at.
- Soft-boiled: the white has set and the yolk still runs.
- Jammy: the center is custardy, the texture a ramen egg is built on.
- Hard-boiled: the yolk is set through, so it will slice or mash.
Compare all methods if you want the three side by side. The same pot does all three. The doneness setting is what changes.
When the timer ends, move the eggs to ice water right away
That stops the cooking, so the center does not keep creeping, and it makes peeling easier. The guides go further on shells that crack, yolks that turn green or gray, how long a boiled egg lasts, why the white sticks, and what changes when the water itself boils cooler.
How to use this calculator
This free boiling eggs at altitude calculator adjusts time for elevation, egg size, doneness, starting temperature, and how many eggs are in the pot. The form above does the math; the steps below are the cooking routine.
- Set your altitude. Type your elevation in meters or feet, or tap Detect My Altitude. Water boils cooler as you go up, so this is the number the calculator needs most.
- Choose size, doneness, and batch. Pick the carton size (medium, large, or extra-large), the yolk you want (soft, jammy, or hard), fridge vs room-temp eggs, hot or cold water start, and how many eggs are in the pot.
- Cook, then chill. Start your timer when the calculator says to add the eggs.
Want the physics? Read the science of boiling eggs. For a pan-side walkthrough of each yolk, see boiling methods ( soft-boiled, jammy, hard-boiled ). When the eggs are done, try ramen eggs, deviled eggs, or egg salad.
Frequently asked questions
Why does altitude change egg boiling time?
At higher elevation, lower air pressure means water boils below 100°C / 212°F. Egg whites and yolks still need the same internal temperatures to set, so they take longer. Enter your altitude (or use Detect My Altitude) and the calculator adds that extra time, so set your own timer to that time instead of using a sea-level chart.
Does egg size change the time?
Yes. A larger egg has more mass, so heat takes longer to reach the yolk. Choose medium, large, or extra-large to match the carton — the time updates as soon as you change it.
What is the difference between soft, jammy, and hard?
Soft is a runny yolk, jammy is custardy (think ramen eggs), and hard is fully set through the center. The calculator times for the yolk texture you pick, not a generic “boil for 10 minutes.” Walk through each one on the methods pages.
See soft-boiled , jammy , and hard-boiled methods, or the methods hub .
How do I make boiled eggs easy to peel?
Immediately put cooked eggs in cold water to make them easy to peel. Ice water for a few minutes also stops them from cooking further in the shell.