Quick answer: One bar is 100 kPa and about 14.5038 psi, so a tyre at 32 psi = 2.2063223 bar.
How it's calculated
The pressure is changed to pascals (newtons per square metre), then to your unit. A bar is exactly 100,000 Pa, a standard atmosphere 101,325 Pa, and 1 psi (one pound-force per square inch) is about 6,894.757 Pa.
Tyre placards in Gulf cars often show both psi and bar (or kPa). Blood pressure is measured in mmHg, and weather maps use millibars, which are the same as hectopascals.
Gauge pressure (tyres, pipes) is measured above the surrounding air pressure; absolute pressure adds about 1 atm.
Worked examples
- Car tyre at 32 psi: 32 psi = 2.2063223 bar
- Sea-level air pressure: 1 atm = 1,013.25 mbar
- Blood pressure of 120 mmHg: 120 mmHg = 15.998686 kPa
Common pressure conversions
| From | To |
|---|---|
| 1 bar | 14.503774 psi |
| 1 psi | 6.8947573 kPa |
| 1 atm | 101.325 kPa |
| 1 atm | 14.695949 psi |
| 1 atm | 759.99989 mmHg |
| 32 psi | 2.2063223 bar |
| 35 psi | 241.31651 kPa |
| 2.2 bar | 31.908302 psi |
| 120 mmHg | 15.998686 kPa |
| 1 kgf/cm² | 14.223343 psi |
Frequently asked questions
How do I convert psi to bar?
Divide by 14.5038. 32 psi ≈ 2.21 bar.
Is a millibar the same as a hectopascal?
Yes. 1 mbar = 1 hPa = 100 Pa.
What is the difference between mmHg and torr?
A torr is 1/760 of an atmosphere (133.3224 Pa); the conventional mmHg is 133.322387 Pa. They differ by less than one part in a million.
What is 2.2 bar in psi?
About 32 psi, a typical front tyre pressure for a family car.
What is normal atmospheric pressure?
1,013.25 hPa (millibars) at sea level. That's 1 atm, 101.3 kPa or about 14.7 psi.
How do I convert kPa to psi?
Divide by 6.895. A tyre placard showing 220 kPa means about 32 psi.