How this calculator works
A kilopascal is 1,000 Pa. The pound per square inch uses the international pound-force, 4.4482216152605 N, acting on a square inch of 0.00064516 m2, which gives 6,894.757293168 Pa. Converting kilopascals to psi therefore multiplies by 1,000 and divides by 6,894.757293168. Tyre placards in Canada and Europe often state kilopascals, while many hand gauges and older manuals use psi.
Formula
psi = kPa x 1000 / 6894.757293168. kPa = psi x 6.894757293168. Equivalently, 1 kPa = 0.145038 psi and 1 psi = 6.89476 kPa.
Worked example
220 kPa = 31.9083 psi. 240 kPa = 34.8091 psi. 100 kPa = 14.5038 psi. 700 kPa = 101.526 psi, which is 7 bar.
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Frequently asked questions
What is a typical car tyre pressure in both units?
Many passenger cars use about 220 to 240 kPa, which is 31.9 to 34.8 psi. Check the placard on the driver door jamb or in the manual rather than relying on a general figure.
Is the psi on a tyre gauge absolute or gauge pressure?
Tyre gauges read gauge pressure, the difference from the surrounding atmosphere. This page converts the number you enter without changing its reference, so a gauge reading stays a gauge reading.
Is the kilopascal an SI unit?
The pascal is the SI unit of pressure and the kilopascal is a prefixed multiple of it. Both are accepted for use with the SI, and kPa is common on weather maps and equipment labels.
Why is psi not exactly 6.9 kPa?
The pound and inch are exact definitions, so one psi is exactly 6,894.757293168 Pa. Rounding that to 6.9 kPa would drift by about 0.08 percent, which matters in high-pressure work.