Tyre Pressure Converter
Convert tyre pressure between psi, bar, kPa, kgf/cm² and atm, and see what a tyre set cold at one temperature reads at another (ideal gas, your ambient).
The pressure in all five units, and with two temperatures the reading at the second one plus the change per 10 °C — gauge pressure, from the placard value you enter.
Example: 32 psi is 2.206 bar, 220.6 kPa, 2.250 kgf/cm²; set at 20 °C it reads about 35.2 psi at 40 °C (≈ 1.6 psi per 10 °C at sea-level ambient).
Five units,
one placard value.
The exact conversion factors, why tyre pressure is gauge pressure, and what temperature does to it.
The units
psi, bar, kPa, kgf/cm² and atm are all fixed multiples of the pascal: 1 psi = 6.894757 kPa, 1 bar = 100 kPa exactly, 1 kgf/cm² = 98.0665 kPa (standard gravity on a kilogram over a square centimetre), 1 atm = 101.325 kPa. A tyre placard's 32 psi is 2.2 bar or 220 kPa; the conversions are exact, only the rounding on the placard is not.
Gauge and temperature
A tyre gauge reads pressure above ambient. The air inside follows the gas law, so at constant volume the absolute pressure scales with absolute temperature: p₂ = (p₁ + p_atm)·T₂/T₁ − p_atm, with temperatures in kelvin and the ambient pressure you enter (about 101.3 kPa at sea level, less at altitude). For a tyre at 32 psi that is roughly 1.6 psi per 10 °C — which is why pressures are set cold and read higher after a drive.
What is not here
Placard values, load and speed tables, and the tyre's own volume change are not embedded — the vehicle label or handbook gives the pressure, and the temperature line is the ideal-gas estimate only. Nothing leaves the browser; the same four anonymous usage counts as the rest of the site apply.
SOURCES
- 1 psi = 6.894757 kPa, 1 bar = 100 kPa, 1 kgf/cm² = 98.0665 kPa, 1 atm = 101.325 kPa; constant-volume ideal gas on absolute pressure p₂ = (p₁ + p_atm)·T₂/T₁ − p_atm
Last reviewed 21 September 2026. How results are checked: How we verify.