Boiling Point at Altitude Calculator

By Bogna Szyk
Last updated: May 17, 2021

This boiling point at altitude calculator can help you find the boiling point of water. Not surprisingly, the temperature at which water starts boiling is not constant and depends on pressure, which in turn is dependent on altitude. In this article, we will present you with the boiling point elevation equation and explain in detain how to calculate the boiling point of water at any altitude.

What is the boiling point?

It is simply the temperature at which water starts boiling - in other words, it changes its state from liquid to gas. This temperature is dependent on pressure and the substance type. Hence, you can be sure that each sample of clear water will start boiling at the same temperature at a given terrain elevation.

Boiling point of water at sea level

You don't have to use our boiling point at altitude calculator to determine the boiling point of water at sea level. It is always the same - 100°C, or 212°F. Actually, the formula for boiling point uses this value as the basis of calculations.

Similarly, the freezing point of water at sea level is a constant value - 0°C or 32°F.

Boiling point elevation equation

Remember that the boiling point of water depends solely on pressure. This boiling point calculator finds the pressure at altitude assuming that the pressure at sea level is constant and equal to 1013 hPa (1.013 bar). This approximation is sufficient for this kind of calculations. If you want to find more precise results, check out our air pressure at altitude calculator.

The formulas for boiling point are: boiling point = 49.161 * ln(pressure) + 44.932

pressure = 29.921 * (1 - 0.0000068753 * altitude)^ 5.2559

Note that these formulas use specific units:

  • boiling point is found in degrees Fahrenheit (°F),
  • pressure is expressed in inches of mercury (inHg),
  • altitude should be put into the equation in the imperial unit - feet (ft).

How to calculate the boiling point

Let's assume you went on a hiking trip to Machu Picchu. You're wondering what temperature you will need to boil water there.

  1. Check the altitude at Machu Picchu (prior to your departure to Peru). It is located at 2430 meters (7970 ft) above sea level.
  2. Input this altitude (in imperial unit) to the formula for pressure:

pressure = 29.921 * (1 - 0.0000068753 * 7970)^ 5.2559 = 22.25 inHg

  1. Now, input this pressure into the boiling point equation:

boiling point = 49.161 * ln(22.25) + 44.932 = 197.44°F

  1. Congratulations! Now you know the boiling point of water at Machu Picchu.
Bogna Szyk
People also viewed…

Equilibrium constant

Need some help calculating the equilibrium constant of a reversible chemical reactions? Having problems with 'how to do it' and 'what for do I need this for'? Click and find the answers to all of your questions!

Henderson Hasselbalch

The Henderson-Hasselbalch calculator is a simple biochemical tool for assessing the pH of a buffer solution.

Pizza size

This calculator will help you make the most delicious choice when ordering pizza.


Use our titration calculator to determine the molarity of your solution.