Convert psi to kilopascals

The formula

kilopascals = psi × 6.8947573

psi to kilopascals — quick reference

A psi figure against a display that counts in kilopascals

Tyre pressure monitoring systems on many cars report in kPa, as do garage compressors across Australia, Japan and much of Asia. A workshop recommendation of 32 psi becomes 221 kPa, and the three-digit result resembles the two-digit one not at all — which is exactly why typing the psi number into a kPa field is such an easy mistake to make.

The scale doubles as a sanity check. Ordinary car pressures land between 200 and 260 kPa; under 150 is flat enough to damage the tyre, over 350 belongs on a van or light truck. A value that looks like a psi figure — 32, or 35 — sitting on a kPa display means the units were confused, not that the tyre has emptied.

Kilopascals sit exactly on the bar scale

100 kPa is precisely 1 bar, so placards printing both are showing one number twice: 220 kPa and 2.2 bar. Anyone moving between European documentation and Asian or Australian equipment can treat kPa as bar with the decimal shifted two places, which leaves psi as the only one of the three needing genuine arithmetic.

All three are gauge pressures, measured against the surrounding air rather than from a vacuum, which is why a flat tyre reads zero instead of the roughly 101 kPa the atmosphere exerts on it. Set pressures cold, before the tyres have warmed, and re-check when the season turns: a 10 degree Celsius drop takes about 10 kPa out of every tyre on the car.

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