Gaugewise / Tire PSI Calculator
Pressure
PSI, bar and kPa in one place, plus what your reading should actually look like once the temperature changes.
A tire filled to 32 PSI at 68°F will read differently once the temperature changes, even with no air added or removed — this is why pressure warning lights often come on during the first cold snap of the year.
How much does tire pressure change with temperature?
Roughly 1 PSI per 10°F (about 5.5°C) as a rule of thumb. This tool calculates it more precisely using the ideal gas law on absolute pressure and temperature.
What PSI should my tires actually be?
Use the number on your vehicle's door-jamb placard or owner's manual — not the number molded into the tire's sidewall, which is the tire's maximum rated pressure, not the recommended one.
How do I convert PSI to bar or kPa?
Multiply PSI by 0.0689476 for bar, or by 6.89476 for kPa.