Tire Pressure Calculator

Switching from your vehicle's Original Equipment Manufacturer (OEM) tire size to a new size requires careful consideration to ensure proper tire inflation and maintain vehicle performance and safety. Finding the proper tire pressure when replacing tires is paramount for several reasons, impacting safety, performance, and the overall lifespan of the tires. Incorrect tire pressure, whether overinflated or underinflated, can lead to uneven tire wear, reduced traction, and potentially dangerous driving conditions. Properly inflated tires ensure optimal contact with the road, enhancing vehicle handling, stability, and braking efficiency. Additionally, the right tire pressure plays a critical role in fuel economy - tires at the correct inflation level minimize rolling resistance, allowing the vehicle to operate more efficiently. Over or underinflation can also increase the stress on tires, leading to premature wear or even catastrophic tire failure, which can be dangerous at high speeds.

Our tire pressure calculator can help you determine if a new tire size can adequately support the load of the original tire, and what pressure should be used on replacement tires. Read more on how to find proper tire pressure when changing to a different tire size.

WARNING: Use of this tire pressure calculator is for reference only. TireSizes.com does not warrant or make any representations regarding the accuracy of or the results of the use of this calculator. Always consult a tire professional tire for accurate tire size and tire inflation settings.

How to Find Proper Tire Inflation When Replacing Tires

It is important to know which standard is applicable for any given tire size designation as the load capacity may differ at any inflation pressure value. Most common tire type standards include Metric, P-Metric, LT-Metric and Flotation.

Here are the steps to determine the correct pressure of a new tire if it matches or exceeds the original load capacity.

• Confirm OEM tire size and cold inflation pressure for your vehicle. You can find both in the vehicle's manual or on tire information placard. The tire information placard can be located on the vehicle door edge, door jam, glove-box door, or inside of the trunk lid.

• Using the tire placard or the vehicle owner's manual, identify the tire size standard used (Metric, P-Metric, LT-Metric or Flotation), as well as its recommended tire pressure.
• User the calculator to select the original tire size along with its load range and recommended pressure value. It will calculate the corresponding load capacity of the original tire size at specified inflation level.
• Now select the new tire size along with its load range.
• Click calculate and check the results. If the new tire has same or greater load capacity compared to the original size, a proper tire pressure value for the new size will be given.

Key Things to Remember

• The maximum inflation pressure indicated on the sidewall of the tire may not be the recommended cold inflation pressure for your vehicle. Refer to your tire information placard or owner's manual for the proper cold inflation pressure and the recommended tire size. The tire information placard can be found on the vehicle door edge, door jam, glove-box door, or inside of the trunk lid.
• The load index may not be used independently to determine replacement tire acceptability for load capacity. An equal or greater load index does not always correspond to equal or greater load capacity at all inflation pressure settings, particularly when comparing P-metric and Euro-metric passenger car tires.
• Tires with the same load index, regardless of tire size, may carry the same load, but not always, and they may require substantially different inflation pressures.
• Make sure the replacement tire has equal or greater load carrying capacity by inflation compared to the OE tire as specified on the vehicle's tire information placard.

Learn everything you need to know about tire inflation and how it works in this ultimate tire pressure guide.

All listed guides, data and/or calculations are for informational purposes only. TireSizes.com does not warrant or make any representations regarding the accuracy of or the results of the use of this information.