Pressure Converter – psi to bar, bar to psi, kPa, atm
Convert pressure units for tyres, weather, diving, compressors and engineering: psi, bar, kilopascal, megapascal, pascal, atmosphere, millibar, mmHg, inHg and torr.
Enter a pressure and pick the units. To convert psi to bar, multiply by 0.0689476 (32 psi = 2.21 bar). For bar to psi, multiply by 14.5038 (2.5 bar = 36.3 psi). 1 bar = 100 kPa, and 1 atm = 1.01325 bar = 14.696 psi.
How to use Pressure Converter
- Type the pressure value.
- Choose the unit you have, such as psi.
- Choose the unit you need, such as bar.
- Read or copy the result.
- See the table for all other units at once.
Common pressure units
| Unit | Equals | Typical use |
|---|---|---|
| 1 bar | 100 kPa · 14.504 psi | tyres, compressors, Europe |
| 1 psi | 6.895 kPa · 0.0689 bar | tyres, US and UK |
| 1 atm | 101.325 kPa · 14.696 psi | chemistry, diving |
| 1 mbar | 100 Pa · 1 hPa | weather maps |
| 1 mmHg | 133.3 Pa | blood pressure |
| 1 inHg | 33.86 mbar | US weather, aviation |
Tyre pressure
Car tyres usually need 2.0–2.5 bar, which is about 29–36 psi; the right value is printed inside the driver’s door or in the manual. Gauges show “gauge pressure”, the pressure above the surrounding air. A flat tyre still contains air at atmospheric pressure but shows 0 on the gauge. Bicycle tyres range from about 2 bar (30 psi) for mountain bikes to 7–8 bar (100–120 psi) for road bikes.
Weather and altitude
Weather maps use hectopascals or millibars — they are the same unit. Average sea-level pressure is 1,013.25 hPa; storms bring values below 1,000 hPa, and high-pressure systems over 1,030 hPa. Pressure falls by about 12 hPa for every 100 m you climb, which is why altimeters can work from air pressure.
Blood pressure and diving
Blood pressure is measured in millimetres of mercury, for example 120/80 mmHg. Divers count in bar or atmospheres: every 10 m of sea water adds about 1 bar, so at 30 m the absolute pressure is about 4 bar.
Gauge vs absolute pressure
Engineering documents sometimes write psig (gauge) or psia (absolute). Absolute = gauge + atmospheric pressure, about 14.7 psi or 1.013 bar at sea level. This converter changes units only; it does not add or remove atmospheric pressure.
Quick answers like 32 psi to bar and 2 bar to psi have their own pages. Other converters: Temperature Converter and Volume Converter.
Compressors and hydraulics
Air compressors are rated in bar or psi, typically 8–10 bar (116–145 psi) for workshop tools. Pressure washers and hydraulic systems use much higher values, often given in bar or megapascals: 150 bar is 15 MPa or about 2,175 psi. Always stay below the maximum working pressure printed on hoses, fittings and tanks.
You may also find these free tools useful: Cooking Measurement Converter, Area Converter and Weight Converter.
Popular calculations
Frequently asked questions
How do I convert psi to bar?
Multiply by 0.0689476. For example, 35 psi × 0.0689476 = 2.41 bar.
How do I convert bar to psi?
Multiply by 14.5038. For example, 2.2 bar = 31.9 psi.
How many kPa is 1 bar?
1 bar is exactly 100 kPa.
What tyre pressure should I use?
Use the value on the sticker inside the driver’s door, usually 2.0–2.5 bar (29–36 psi) for cars.
Are hPa and mbar the same?
Yes. 1 hectopascal equals 1 millibar.
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