Convert pressure measurements instantly across all major metric, imperial, and scientific scales: Pascal (Pa), Kilopascal (kPa), Megapascal (MPa), Bar, Millibar (mbar), Pounds per Square Inch (psi), Standard Atmosphere (atm), Millimetre of Mercury (mmHg), Torr, and Inch of Mercury (inHg).
Converting bar in to psi (or bar a psi conversion) is one of the most frequent calculations in automotive care, pneumatic machinery, HVAC, and industrial engineering. While bar is widely used throughout the UK, continental Europe, and international metric standards, psi (pounds per square inch) remains the standard measure in the United States and classic automotive guides.
Pressure in PSI = Pressure in Bar × 14.503774
Reverse Formula: Pressure in Bar = Pressure in PSI ÷ 14.503774 (or × 0.0689476)
| Bar | PSI (Exact) | PSI (Rounded) | Typical Application / Real-World Context |
|---|---|---|---|
| 1.0 bar | 14.5038 psi | 14.5 psi | Atmospheric base level (~100 kPa) |
| 1.8 bar | 26.1068 psi | 26.1 psi | Light trailer tyre / small vehicle rear tyres |
| 2.0 bar | 29.0075 psi | 29.0 psi | Compact car cold tyre pressure |
| 2.2 bar | 31.9083 psi | 31.9 psi | Sedan front tyre rating (equivalent to 220 kPa) |
| 2.3 bar | 33.3587 psi | 33.4 psi | Standard passenger car cold pressure (230 kPa) |
| 2.4 bar | 34.8091 psi | 34.8 psi | UK SUV and family estate cold tyre recommendation |
| 2.5 bar | 36.2594 psi | 36.3 psi | Fully loaded vehicle rear tyres (250 kPa) |
| 3.0 bar | 43.5113 psi | 43.5 psi | Space-saver spare tyre / commercial van tyres |
| 4.2 bar | 60.9159 psi | 60.9 psi | Temporary spare tyre ("donut") standard mark |
| 8.0 bar | 116.0302 psi | 116.0 psi | Road bicycle tyre / workshop air compressor line |
For existing dedicated single-value guides, see our complete reference for 1 Bar to PSI Conversion.
Vehicle manufacturers in Europe, Japan, and international markets publish recommended tyre inflation figures in kilopascals (kPa) inside the door jamb sticker or fuel filler flap. Drivers using UK or US air pumps must convert these figures into psi. Below are the precise conversions for the three most common automotive tyre specifications:
31.91 PSI
Formula: 220 ÷ 6.894757 = 31.908 PSI.
In Bar: 2.20 bar.
Usage: Standard front tyre pressure for compact and mid-size sedans under normal vehicle load.
33.36 PSI
Formula: 230 ÷ 6.894757 = 33.359 PSI.
In Bar: 2.30 bar.
Usage: Most common all-season tyre pressure recommendation for crossovers, hatchbacks, and saloon cars.
36.26 PSI
Formula: 250 ÷ 6.894757 = 36.259 PSI.
In Bar: 2.50 bar.
Usage: Heavy luggage/full passenger load rating, SUV rear axles, and motorway high-speed driving mode.
| Kilopascals (kPa) | PSI (Exact) | PSI (Pump Gauge Setting) | Bar Equivalent |
|---|---|---|---|
| 100 kPa | 14.5038 psi | 14.5 psi | 1.00 bar |
| 200 kPa | 29.0075 psi | 29.0 psi | 2.00 bar |
| 210 kPa | 30.4579 psi | 30.5 psi | 2.10 bar |
| 220 kPa | 31.9083 psi | 32.0 psi | 2.20 bar |
| 230 kPa | 33.3587 psi | 33.5 psi | 2.30 bar |
| 240 kPa | 34.8091 psi | 35.0 psi | 2.40 bar |
| 250 kPa | 36.2594 psi | 36.5 psi | 2.50 bar |
| 300 kPa | 43.5113 psi | 43.5 psi | 3.00 bar |
| 350 kPa | 50.7632 psi | 51.0 psi | 3.50 bar |
In process engineering, oil & gas, steam generation, and industrial hydraulics, distinguishing between gauge pressure (barg, psig) and absolute pressure (bar(a), psia) is vital to avoid catastrophic piping calculation mistakes:
| Gauge Reading (barg) | Gauge Reading (psig) | Absolute (bar a) | Absolute (psia) |
|---|---|---|---|
| 0 barg (Open air) | 0 psig | 1.013 bar(a) | 14.696 psia |
| 1 barg | 14.504 psig | 2.013 bar(a) | 29.200 psia |
| 2 barg | 29.008 psig | 3.013 bar(a) | 43.704 psia |
| 6 barg (Plant air) | 87.023 psig | 7.013 bar(a) | 101.719 psia |
| 10 barg (Steam line) | 145.038 psig | 11.013 bar(a) | 159.734 psia |
| 20 barg (Hydraulics) | 290.075 psig | 21.013 bar(a) | 304.771 psia |
The Pascal (Pa) is the SI base unit for pressure, defined as 1 newton per square metre (1 N/m²). Cross-reference all standard pressure scales below:
| Unit | Pascal (Pa) | Kilopascal (kPa) | Bar | PSI | Atmosphere (atm) | Torr / mmHg |
|---|---|---|---|---|---|---|
| 1 Pa | 1 | 0.001 | 0.00001 | 0.000145 | 9.8692×10-6 | 0.007501 |
| 1 kPa | 1,000 | 1 | 0.01 | 0.145038 | 0.009869 | 7.5006 |
| 1 bar | 100,000 | 100 | 1 | 14.5038 | 0.986923 | 750.064 |
| 1 psi | 6,894.757 | 6.89476 | 0.068948 | 1 | 0.068046 | 51.7149 |
| 1 atm | 101,325 | 101.325 | 1.01325 | 14.6959 | 1 | 760.000 |
| 1 mmHg | 133.3224 | 0.133322 | 0.001333 | 0.019337 | 0.001316 | 1.000 |
How do I convert 220, 230, and 250 kPa to psi for tyre inflation?
Divide kilopascals by 6.894757. 220 kPa equals 31.91 psi (round to 32 psi on mechanical gauges). 230 kPa equals 33.36 psi (round to 33.5 psi). 250 kPa equals 36.26 psi (round to 36.5 psi). Always check pressures when tyres are cold for maximum safety.
What is the difference between bar, barg, and psig?
Bar is an absolute pressure unit unless qualified. Barg refers specifically to gauge pressure (bar gauge) above atmospheric pressure. Psig is pounds per square inch gauge. Because both barg and psig place zero at atmospheric pressure, converting between them is direct: 1 barg = 14.5038 psig.
How do I convert bar in to psi manually?
Multiply the bar reading by 14.5. For quick mental estimates: 2 bar is ~29 psi, 2.2 bar is ~32 psi, and 2.5 bar is ~36 psi. For exact scientific requirements, multiply by 14.503774.
Why do scientific institutions specify Pascal (Pa)?
The Pascal is the SI derived unit of pressure defined by the BIPM and NIST as 1 newton per square metre. 1 bar is exactly 100,000 Pascals (100 kPa), designed to approximate Earth's atmospheric pressure while keeping clean decimal metric scaling.
