Boiling Point At Altitude Calculator
Our chemical thermodynamics calculator computes boiling point at altitude accurately. Enter measurements for results with formulas and error analysis.
Formula
P = P0 * (1 - 2.25577e-5 * h)^5.25588; ln(P1/P2) = (deltaH/R) * (1/T2 - 1/T1)
The barometric formula calculates atmospheric pressure P at altitude h (meters) from sea-level pressure P0. Then the Clausius-Clapeyron equation relates the pressure ratio to boiling temperature, where deltaH is the enthalpy of vaporization (40,660 J/mol for water) and R is the gas constant (8.314 J/mol-K).
Worked Examples
Example 1: Boiling Water in Denver, Colorado
Problem: Denver sits at approximately 1,609 meters (5,280 feet) above sea level. What is the boiling point of water there?
Solution: Pressure at 1,609m: P = 101.325 * (1 - 0.0000225577 * 1609)^5.25588 = 83.44 kPa\nUsing Clausius-Clapeyron: ln(83.44/101.325) = (40660/8.314) * (1/T2 - 1/373.15)\nSolving: T2 = 368.03 K = 94.88 C\nTemperature drop: 100 - 94.88 = 5.12 C
Result: Boiling point in Denver: 94.88 C (202.78 F) — about 5.1 C below sea level
Example 2: Boiling Water on Mount Kilimanjaro Summit
Problem: Mount Kilimanjaro peak is at 5,895 meters. What temperature does water boil at the summit?
Solution: Pressure at 5,895m: P = 101.325 * (1 - 0.0000225577 * 5895)^5.25588 = 49.45 kPa\nUsing Clausius-Clapeyron: ln(49.45/101.325) = (40660/8.314) * (1/T2 - 1/373.15)\nSolving: T2 = 353.96 K = 80.81 C\nTemperature drop: 100 - 80.81 = 19.19 C
Result: Boiling point at Kilimanjaro summit: 80.81 C (177.46 F) — nearly 20 C below sea level
Frequently Asked Questions
Why does boiling point decrease at higher altitudes?
Boiling occurs when the vapor pressure of a liquid equals the surrounding atmospheric pressure. At higher altitudes, atmospheric pressure is lower because there is less air above pushing down. With less pressure on the liquid surface, water molecules need less kinetic energy to escape into the gas phase, so the liquid boils at a lower temperature. For every 150 meters of elevation gain, the boiling point of water drops by approximately 0.5 degrees Celsius. At the summit of Mount Everest (8,849 meters), water boils at roughly 70 degrees Celsius instead of the usual 100 degrees at sea level.
How does altitude affect cooking times?
Since water boils at a lower temperature at higher altitudes, food cooked in boiling water takes longer to cook because the water is not as hot. At 2,000 meters elevation, water boils at about 93 degrees Celsius, which means pasta, rice, and vegetables take noticeably longer to cook. As a general rule, for every 300 meters above sea level, you should increase cooking time by about 5 to 10 percent. Pressure cookers are particularly useful at high altitude because they trap steam and raise the internal pressure, restoring the boiling point closer to 100 degrees Celsius and cooking food at normal speed.
How do I interpret the result?
Results are displayed with a label and unit to help you understand the output. Many calculators include a short explanation or classification below the result (for example, a BMI category or risk level). Refer to the worked examples section on this page for real-world context.
Can I use Boiling Point At Altitude Calculator on a mobile device?
Yes. All calculators on NovaCalculator are fully responsive and work on smartphones, tablets, and desktops. The layout adapts automatically to your screen size.
Is my data stored or sent to a server?
No. All calculations run entirely in your browser using JavaScript. No data you enter is ever transmitted to any server or stored anywhere. Your inputs remain completely private.
How do I get the most accurate result?
Enter values as precisely as possible using the correct units for each field. Check that you have selected the right unit (e.g. kilograms vs pounds, meters vs feet) before calculating. Rounding inputs early can reduce output precision.