Above about 3,000 feet, add one minute to any boiled egg time; above 5,000 feet, add two; above 7,000, add three and expect some variance. Water boils cooler up there — around 202°F in Denver — so eggs cook slower even in a rolling boil.
13 minutes, large egg, straight from the fridge, into boiling water. Fully set, no grey ring.
Fully set, no grey ring
Pick your city first
13:00
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Start it the moment the eggs go into the boiling water.
Method, altitude, and other eggs
Only matters above about 3,000 ft. If your city isn’t listed, you’re fine on the standard times. Learn more
From the fridge, into already-boiling water. Tap any time to start it.
Doneness
Medium
Large
Extra large
What you get
Soft
Runny yolk, set whites
Jammy
Custardy centre, the ramen-egg standard
Medium
Set edge, soft fudgy centre
Hard
Fully set, no grey ring
Why altitude changes a boiled egg
Water boils when its vapour pressure matches the air pressure above it. Less air pressure — which is what altitude is — means water hits that point at a lower temperature. At sea level water boils at 212°F. In Denver at 5,280 feet it boils around 202°F. In Bogotá at 8,660 feet, closer to 197°F. Lhasa, La Paz, Cusco: lower still.
Here’s the part that trips people up: the water looks identical. A rolling boil at 197°F bubbles exactly like a rolling boil at 212°F. But the egg only cares about temperature, and egg proteins set on a schedule — yolk proteins begin thickening around 150°F and firm through the 160s. Cooler water walks the egg through those thresholds more slowly, so every time on a standard chart runs short. The egg you wanted jammy comes out soft; the hard boiled one has a wet centre.
Turning the burner up does nothing, by the way. Once water is boiling, extra heat makes more steam, not hotter water. The boiling point is a ceiling, and at altitude the ceiling is lower. The only lever left is time.
How much time to add
Sea level to 3,000 ft: nothing — the effect is real but smaller than your egg-size variance. 3,000–5,000 ft: add about one minute. 5,000–7,000 ft: about two. Above 7,000 ft: three minutes as a starting point, and expect to fine-tune, because above that height small pressure differences (even the day’s weather) start to show up in the yolk.
Soft and jammy eggs need proportionally more care than hard ones — their doneness windows are under a minute wide, so at serious altitude, cook one test egg, note what you get, and adjust in 30-second steps. Then write your number down; your kitchen’s number beats any chart’s.
Or just tell the timer where you are
The timer on this page has a city selector — pick Denver or Bogotá or Kathmandu and it applies the right adjustment automatically, on top of your egg size and doneness. If your town isn’t listed, choose “somewhere else” and enter your elevation; a quick search for “your town elevation” finds it.
Altitude questions
At what altitude do I need to start adjusting?
About 3,000 feet. Below that, the boiling-point difference is smaller than the difference between a large and extra-large egg, so the standard times hold. Most of the US population lives below this line; Denver, Salt Lake City, Albuquerque, and most of the Mountain West live above it.
Does altitude affect other egg methods too?
Anything that cooks with boiling water or steam, yes — stovetop, steamed, kettle. Air fryer and oven methods are unaffected: dry heat at 270°F is 270°F at any elevation. A pressure cooker largely cancels altitude out, which is one reason the Instant Pot method is popular in mountain towns.
Why doesn’t turning up the heat fix it?
Because boiling water can’t get hotter than its boiling point — extra burner heat just boils it away faster. At altitude that ceiling is lower, and no stove setting raises it. Only a sealed pressure vessel does, which is exactly what a pressure cooker is.
Is this why my baking fails at altitude too?
Related physics, different failure. Baking suffers from faster evaporation and over-expanding leaveners; eggs suffer purely from cooler water. The egg fix is simpler — just add time.