Effect of Altitude on Tire Air Pressure

by Milton Kazmeyer

Keeping your tires properly inflated reduces wear and tear on your car and saves gas. Unfortunately, any substantial change in altitude can affect your tire pressure and lead to problems.

Air Pressure

Air pressure is measured in pounds per square inch, or psi. Air pressure is 14.7 psi at sea level and decreases as you ascend.

Altitude Changes

If you inflate your tires at sea level, the air inside is pressing against 14.7 psi from the air outside. At higher altitudes, the same amount of air will have more pressure because the outside force is reduced.


The result of lower pressure at altitude means that less air will be needed to properly inflate your tires than at sea level, and tires inflated properly at a lower altitude may now be overfilled.


Anytime you experience a substantial change in altitude, you should check your tire psi and adjust accordingly, adding more air when descending and releasing it when moving higher.

Temperature Changes

It's also important to note that warmer temperatures will cause the air in your tires to expand, increasing the pressure, and colder temperatures will have the opposite effect. Keep this in mind when making adjustments.

About the Author

Milton Kazmeyer has worked in the insurance, financial and manufacturing fields and also served as a federal contractor. He began his writing career in 2007 and now works full-time as a writer and transcriptionist. His primary fields of expertise include computers, astronomy, alternative energy sources and the environment.

Photo Credits

  • photo_camera Image by Flickr.com, courtesy of Saquan Stimpson