What is the conversion between tire pressures?

Tire pressure conversions between bar, psi, and kPa are straightforward once you know the ratios. The most common units are bar (metric) and psi (imperial). One bar equals 14.5038 psi, and 1 psi equals 0.0689 bar. Kilopascals (kPa) are also used, with 1 bar equalling 100 kPa.

For example, if your car's recommended pressure is 2.2 bar, the equivalent in psi is roughly 32 (2.2 x 14.5). Conversely, a tyre marked 35 psi converts to about 2.4 bar (35 x 0.0689).

1. To convert bar to psi: multiply by 14.5.
2. To convert psi to bar: multiply by 0.0689.
3. To convert bar to kPa: multiply by 100.

Most modern cars display recommended pressures in both bar and psi, often found on a sticker inside the driver’s door or fuel flap. Always check your vehicle’s manual for exact figures, as incorrect pressures can affect handling, fuel efficiency, and tyre wear.

There are generally five units for measuring air pressure: kg/cm², bar, Kpa, psi, and atmospheric pressure. The conversion relationships between them are as follows: 1kg/cm²=0.98bar=98.0665Kpa=14.2Psi; 1 atmospheric pressure=1.03327 kg/cm².

For daily tire pressure measurements, the conversion relationships can be simplified as: 1(bar)=1.02(kg/cm²)=14.5(psi)=100Kpa; 1(kg/cm²)=0.98(bar)=14.2(psi); 1(psi)=0.069(bar)=0.07(kg/cm²); 1(kpa)=0.01(bar)=0.0102(kg/cm²).

To maintain your tires properly, regularly use a tire pressure gauge to check the tire pressure, ensuring the tires are used at the correct pressure.