Kilopascals to PSI Converter

Kilopascals turn up on tyre placards, on digital inflators that cycle between kPa, bar and psi, and in engineering data sheets. If the number you are looking at is in the low hundreds, such as 220 or 250, it is almost certainly kPa, not Pa or psi.

• 220 kPa = 31.9083 psi
• 230 kPa = 33.3587 psi
• 250 kPa = 36.2594 psi
• 300 kPa = 43.5113 psi

A kilopascal is one hundredth of a bar, so 220 kPa and 2.2 bar are the same pressure and give the same psi. If a placard shows kPa and your inflator offers bar, you only need to move the decimal point two places.

The exact factor here is 1 kPa = 0.14504 psi. When you have no phone to hand, pick the shortcut that matches how close you need to be. Errors below are computed against the converter, for 240 kPa (34.8091 psi):

Dividing by 7 is the easiest and is fine for a rough check, but it reads about half a psi low at tyre pressures. Multiplying by 0.145 is the one to use when you are setting a value.

The most damaging mistake with pascals is the prefix. A hydraulic or gas-cylinder rating in megapascals is a thousand times larger than the same digits in kilopascals. The pressure menu offers Pa, kPa, bar, psi, atm and mmHg, but not MPa, so multiply an MPa figure by 1,000 and enter it as kPa: 0.7 MPa is 700 kPa, which converts to 101.53 psi. For raw pascal values, switch the From menu to Pa instead of dividing by hand.

Small values are shown to five significant figures. A 5 kPa reading, the kind you see on low-pressure ducts or fans, comes out as 0.72519 psi.

Barometric pressure is absolute, measured from a vacuum, and sits near 101 kPa at sea level. Converting 101.3 kPa gives 14.6923 psi. A tyre gauge would read that same air as zero, because it reports pressure above the air around it. Both are valid kPa figures; they just start from different zero points, and this converter does not add or remove that offset.