PSI to Bar Converter

Quick Answer

Last updated: 11 November 2026 ·How we calculate this: NIST pressure conversion factors

How This PSI to Bar Converter Works

US tire gauges, air compressors and pressure washers read in psi, while European cars, bikes, scuba gear and espresso machines use bar or kPa. Choose the unit on your gauge, enter the reading and press Calculate. The converter shows the same pressure in psi, bar, kPa, MPa, atmospheres and pascals.

How to Use the PSI to Bar Converter

1. Choose the unit your gauge or spec uses.
2. Enter the pressure.
3. Press Calculate.
4. Read the pressure in psi, bar, kPa, MPa, atm and Pa.

Pressure Conversion Formulas

• psi: 1 psi = 1 pound-force per square inch = 6894.757 Pa
• bar: 1 bar = 100,000 Pa = 100 kPa exactly
• bar from psi: bar = psi × 0.0689476
• psi from bar: psi = bar × 14.5038
• Atmosphere: 1 atm = 101.325 kPa = 1.01325 bar = 14.696 psi

Key Terms

• psi: pound-force per square inch.
• bar: 100,000 pascals, about one atmosphere.
• Kilopascal (kPa): 1,000 pascals, the SI unit on many tire labels.
• Atmosphere (atm): 101,325 Pa, standard sea-level air pressure.
• Gauge pressure: pressure above the surrounding air (psig, barg).

Worked Example

A car’s door sticker says 2.4 bar. What should a US gauge read?

• 2.4 × 14.5038 = 34.8 psi
• In kPa: 2.4 × 100 = 240 kPa
• So inflate to about 35 psi when the tires are cold.

Going the other way, a 90 psi air compressor setting is 90 × 0.0689476 = 6.21 bar.

Real-Life Examples

• Car tires: 2.2 bar is 31.9 psi.
• Bike tires: 100 psi is 6.89 bar.
• Espresso: 9 bar is 130.5 psi.
• Scuba tanks: 3,000 psi is 207 bar.

PSI vs Bar

• psi: pounds per square inch, used in the US.
• bar: 100 kPa, close to one atmosphere, used in Europe.
• Size: 1 bar = 14.5038 psi; 1 psi = 0.06895 bar.

PSI to Bar Chart

1 psi = 6.894757 kPa; 1 bar = 100 kPa.

Gauge vs Absolute Pressure

Most gauges read gauge pressure: zero means the same as the air around you. A flat tire reads 0 psi even though the air inside is at about 14.7 psi absolute. Scientific and engineering work sometimes uses absolute pressure, written psia or bara, which adds the atmosphere. When converting, keep the type the same: 30 psig is 2.068 barg, and 30 psia is 2.068 bara; the units change but the reference does not.

The kilopascal is the SI unit used on tire placards in Canada, Australia and much of Asia, and the bar is common in Europe because 1 bar is close to air pressure at sea level. MPa is used for high pressures such as hydraulic systems and concrete strength (1 MPa = 145 psi). Atmospheric pressure itself changes with weather and altitude, so tire pressure should always be checked cold with a gauge, not estimated.

Tire pressure also changes with temperature: as a rough guide it drops about 1 psi (0.07 bar) for every 10 °F (about 5.6 °C) fall in air temperature, which is why tires often look low on the first cold morning of autumn. Check and adjust them monthly and before long trips, using the pressure on the driver’s door sticker rather than the maximum printed on the tire sidewall. The sidewall number is the most the tire can safely hold, not the pressure the car maker recommends for grip, braking and wear.

Common Mistakes to Avoid

• Mixing gauge and absolute pressure. Add 14.7 psi only when converting to absolute.
• Using 15 psi per bar. It is 14.5; 35 psi is 2.41 bar, not 2.33.
• Confusing bar and atm. 1 atm is 1.013 bar.
• Reading kPa as bar. 240 kPa is 2.4 bar.
• Checking hot tires. Placard pressures are for cold tires.

Frequently Asked Questions

References & Sources