Tire Pressure Temperature Calculator – Avoid Accidents

The tire pressure temperature calculator helps to diagnose tire leaks, the risk of tire explosion during exposure to extreme heat or cold, and even a tire’s weight limit before an accident. Look into your vehicle’s owner’s manual to determine the ideal tire pressure temperature for you; the standard is 32 PSI.

Check out the car salesmen earnings calculator here. Visiting a auto repair shop? ask for your free courtesy car. Here’s how to get the loaner vehicle.

 Disclaimer: Online tire pressure calculators are for estimations only. Results may not always accurate  

The air in your tires is influenced by temperature and hence, the weather. The air in your tires takes up more volume while the temperature is warm, whereas the air takes up less volume while the temperature is low. The inflation pressure typically changes by 1 to 2 psi for every 10 degrees change in the temperature.

As you drive the car and the tires warm-up, the tires’ pressure can rise by one psi every twenty minutes. When the seasons’ change and the temperatures vary, it is important to know what can happen to your tire. 

Online tire pressure temperature calculators are available to help you calculate tire pressure temperature easily, as long as you know your last tire pressure and the temperature at that time.

tire pressure temperature calculator

Tire pressure is higher when it’s hotter and lower when it’s colder. It’s not the tires that carry the car’s weight, it’s the air in the tires, and it’s typically stored at around 32 PSI (Pounds per Square Inch). The temperature of the air around the tire, the temperature of the tires themselves, exposure to heat, and air leakage are some of the factors that affect tire pressure.

The cold inflation pressure is the pressure to be used when inflating the tires in the cold. It is usually displayed in the car. Tyre pressure differs during the course of the day and period of use. Cold air implies less weight on the tires relative to hot weather. A larger part of the tires is in touch with the road, and this increases fuel usage. The tire pressure decreases by roughly 0.19 PSI with every decrease of 1 degree Celsius.

The effect of the sun on tyre pressure will make a difference of up to 15 percent. Those black tires consume the heat in the bright sun, and it passes on to the air within. It is probable to provide a 10 PSI difference, considering the calculations and atmospheric pressure. If you fill your car tires on a freezing night when they are cold, and you drive them on hard, dry roads in the scorching sun at high speeds, you would be causing an increase in tire pressure.

The ideal gas law would be the foundation of the derivation.


Equation 1 (Ideal Gas Law)


  • P is the absolute (not gauge) pressure.
  • V is the internal volume of the tire and rim combination.
  • n is the amount of air in the tire. We won’t worry about the units here; you can think of n as being the mass of the air, if you like.
  • R is a constant. The value depends on the units we use; again, we won’t worry about it here.
  • T is the absolute (i.e. above absolute zero) temperature.

 I would be making the following assumptions:

  • For air under pressure, the ideal gas law is true.
  • For low-pressure gases and gas mixtures, the ideal gas rule performs well. Still, it becomes less specific when temperatures climb. 
  • With pressure, the tire’s volume varies insignificantly.
  • Tires are very stable (e.g., they may have steel cords embedded in them). Usually, extreme under-inflation is very visible because the rubber of the tire is sagging.
  • Tires that are approaching maximum inflation differ little in volume when pressure changes.

Given the principles mentioned above, we can extract an equation indicating that the percentage shift in a tire’s air pressure is inversely proportional to the tire’s air temperature (Equation 1).

Equation 2 (Ideal Gas Law)

  • The absolute temperature of the air in the tire is T.
  • As a function of temperature, p(T) is the air pressure of the tire.
  • \Delta p\% is the percentage difference in the temperature of the tire pressure.
  • Extract Equation 1

We can add Equation 2 to a common tire pressure scenario to give us the rule of thumb in Figure 2. The case involving tire pressure is:

The ambient temperature of the tire is 20 °C (68 °F).
Sea Air Pressure level 14. Oh. 7 psi.
Nominal 40 psi tire pressure (gauge pressure)

Mathcad transforms temperatures to an absolute scale automatically (e.g., Kelvin). So realize that this temperature is being transformed into Kelvin when you see a term like “(-20)°F”.

We see in the illustration that the temperature difference in the tire pressure is around one psi for each temperature change of 10 ° F for a tire pressure of 40 psi at 68 ° F. There are two different air temperatures in Figure 2.

You can find that the pressure change with temperature rises with a lower reference temperature with specified tire pressure.

Using one of the two techniques detailed below, you can determine tire pressure temperature. 

Use the Weight of the Vehicle Method

  • The tire manufacturer determines the optimal tire pressure for different loads. You can easily get your tire chart online from the tire shop.
  • Getting the front and rear weight of your truck is the next move. By loading materials into the vehicle, filling the gas tanks, and getting more passengers, you’ll get a more reliable result.
  • You have to weigh and calculate your front tires and then, separately, your rear tires. You can use the compact scales in a race shop near you to get these weights easily.
  • You’ll have to take three weight readings at the truck stop. The first one is for when only the front tires are on the scale. The second reading is taken when all tires are on the scale, and the third is for the back tires. The sum of the front and back tires’ readings should be equal to the total weight reading.
  • Next, to weigh each tire, divide the weight on the front tires by two. And do the same with the reading for the rear tire.
  • Finally, recheck the load chart, estimate the calculated value to the nearest tire pressure and add another 10 percent.
  • Check your results by weighing the tires and applying friction to balance them. If there are deviations, apply pressure to balance it out, as mentioned. From front to back, the profiles should look the same.
  • The value of this mechanism is that the optimum strain can end up with you. Optimum means you match the reliability of petrol, the consistency of your journey, the output of handling and braking, and the uniformity of tread wear.

Use the Sidewall Method

  • As seen on your sidewall, locate the highest pressure and let that be your street pressure. Until you have time to make a more precise estimate, it will suffice. 
  • Remember that this generally implies that the tire pressure, particularly if the truck is not holding a load, maybe too high. 
  • The value of this maximum pressure from the sidewall is that it’s secure. You can also get a fuel efficiency gain from it since it would minimize the rolling resistance.
Wrap Up

Having a tire pressure testing routine will help prolong your tires’ life and allow you to be conscious of small problems before they become major issues. Use the free online tire pressure calculator and a pressure gauge. Manufacturers of tires have a recommended psi, which determines the optimum amount of pressure for your vehicle and its tires. The psi number is, however, set for when your tires are cool. 

If you keep your tires underinflated, it can cause you to lose steering power, raise friction, cause your tires to wear further, and reduce your vehicle’s reliability while using petrol. It’s necessary to monitor the tire pressure once a month to prevent the effects of over-and under-inflated tires. Your tires can always constantly lose pressure even when there are no leaks. Chances are, once your pressure is considerably poor, your car may not signal you, so it’s necessary to inspect your tires and know your tire pressure temperature manually.

Read my posts on h1 bulb, h7 bulb, low and high beam light, engine oil here.

Scroll to Top