Boiling Point at Altitude Calculator

How Altitude Affects Boiling Point

Water boils when its vapor pressure equals atmospheric pressure. At higher altitudes, atmospheric pressure is lower — so water boils at a lower temperature. This affects cooking, sterilization, and hot drinks.

Boiling Point Formula: T_boil(°C) = 100 − (Altitude in meters / 294)

A more accurate approximation: T_boil(°C) ≈ 100 − 0.003353 × Altitude(m)

Worked Example: Denver, Colorado (altitude 1,609 m):

• T_boil = 100 − (1609 / 294) = 100 − 5.47 = 94.5°C (202.1°F)

Kathmandu, Nepal (1,400 m):

• T_boil ≈ 100 − (1400 / 294) = 95.2°C

Mount Everest Base Camp (5,364 m):

• T_boil ≈ 100 − (5364 / 294) = 81.7°C (179°F)

Effect on Cooking:

• Pasta takes longer: water at 94°C vs 100°C is noticeably slower to cook starch
• Eggs: soft-boil time increases ~15–20% per 1,000m elevation
• Baking: liquids evaporate faster at altitude; reduce leavening agents by 25%
• Sterilization: boiling water at altitude does NOT kill all pathogens reliably above 3,000m — use a pressure cooker

Pressure Cooker at Altitude: A pressure cooker raises boiling point above 100°C regardless of altitude. At 15 psi overpressure, boiling point ≈ 121°C — sufficient for proper sterilization even at high altitude.