Cooking Altitude Adjustment Calculator

Altitude cooking adjustment is necessary because water boils at progressively lower temperatures as elevation increases.
Thinner air presses down on the surface of the water less hard, so it takes less heat to push molecules out of it, and the water reaches a rolling boil at a lower temperature. That affects baking, boiling, and pressure cooking, and it affects each of them differently.

Boiling Point by Altitude Formula:

Boiling Point (°F) ≈ 212 − (0.00184 × Elevation in feet)

Or in Celsius: Boiling Point (°C) ≈ 100 − (0.00336 × Elevation in meters)

Boiling point reference:

Baking adjustments at high altitude (above 3,500 ft):

Why baking changes at altitude:

• Gases in batter expand faster in low pressure → cakes rise too quickly, then collapse
• Liquids evaporate faster → cakes dry out before fully set
• Leavening reacts more vigorously → reduce baking powder/soda
• Weaker structure cannot hold the faster rise → a spoonful or two of extra flour per cup stiffens the batter enough to keep it up

Two different clocks, and they run opposite ways. This trips people up constantly, so it is worth being precise about which is which.

In the oven, the fix is a hotter, shorter bake. Raising the temperature sets the structure before the over-eager rise has time to collapse, and that hotter oven finishes the job sooner, so start checking well before the recipe time is up.

In a pot of water, the opposite happens. Water boils cooler up here, so food sits in cooler liquid and needs longer. The rule you will see everywhere is about 10% more time per 1,000 feet, and it is a reasonable working figure for eggs and vegetables. Be aware it is a rule of thumb rather than a measurement: how much longer boiled food actually needs is genuinely not settled, and the pasta cook time at altitude calculator shows the spread between the two standard ways of modeling it. At 7,000 ft a “10-minute” hard-boiled egg wants something like 14 to 16 minutes.

Pressure cookers at altitude: Increase pressure cooker cooking time by 5% for every 1,000 ft above 2,000 ft.

Not every recipe cares. Cakes, quick breads, and anything leavened with baking powder suffer most, because they depend on a rise that altitude wrecks. Yeast breads are more forgiving as long as you watch the proof and do not let it run away. Cookies, brownies, pie crust, and most stovetop work barely notice. If you are only going to adjust one thing, adjust the cake.