The exact factor, and the shortcut on the tyre wall
One psi equals 6.895 kPa, so one kPa is 0.145 psi. Both are printed side by side on most tyre placards. For a quick estimate, treat 1 psi as about 7 kPa: divide kPa by 7 to get psi, or multiply psi by 7 for kPa. That stays within roughly 2%.
Common pressures both ways
| kPa | psi | Where you see it |
|---|---|---|
| 1 kPa | 0.145 psi | — |
| 101.3 kPa | 14.7 psi | atmosphere at sea level |
| 200 kPa | 29.0 psi | soft car tyre |
| 220 kPa | 31.9 psi | typical car tyre |
| 240 kPa | 34.8 psi | firm / loaded car tyre |
| 700 kPa | 101.5 psi | air compressor / power tools |
Most passenger cars want 200–280 kPa (29–40 psi). Always follow the figure on the door jamb, not the number moulded into the tyre, which is the maximum.
Two traps worth knowing
- Gauge vs. absolute. A tyre gauge reads pressure above the atmosphere. Absolute pressure adds the atmosphere on top, about 101 kPa or 14.7 psi. A tyre at 32 psi gauge is roughly 47 psi absolute.
- bar is close but not kPa. 1 bar is 100 kPa, or 14.5 psi, and is common on European gauges. It is not interchangeable with the atmosphere, which is 101.3 kPa.
Common questions
How do I convert kPa to psi?
Multiply the kPa figure by 0.145. For example 220 kPa is 220 times 0.145, about 31.9 psi. To go back, multiply psi by 6.895.
What is 32 psi in kPa?
32 psi is about 220 kPa, a typical car tyre pressure. Multiply psi by 6.895 for the exact figure.
Is there a quick mental shortcut?
One psi is close to 7 kPa, so divide kPa by 7 for a fast psi estimate, or multiply psi by 7 for kPa. It is within about 2%, fine for checking tyres.
