Bar to Pascal Converter (bar ⇄ Pa)

How to convert bar to pascal

The bar is a convenient pressure unit commonly used in engineering, meteorology, and industry. The pascal (Pa) is the SI base unit of pressure. The relationship between them is defined exactly:

Because this is an exact definition, conversions between bar and pascal are simple multiplications or divisions by 100,000.

Formula: bar to pascal

where:

• P_Pa is the pressure in pascal
• P_bar is the pressure in bar

Formula: pascal to bar

Worked examples

Example 1 – 2.5 bar to pascal

Convert 2.5 bar to pascal.

1. Use the formula: P_Pa = P_bar × 100,000
2. P_Pa = 2.5 × 100,000 = 250,000 Pa

Answer: 2.5 bar = 250,000 Pa.

Example 2 – 101,325 Pa to bar

Convert 101,325 Pa (standard atmospheric pressure) to bar.

1. Use the formula: P_bar = P_Pa ÷ 100,000
2. P_bar = 101,325 ÷ 100,000 = 1.01325 bar

Answer: 101,325 Pa ≈ 1.01325 bar.

Understanding bar and pascal

What is a pascal (Pa)?

The pascal is the SI unit of pressure, defined as one newton of force applied over one square meter:

In practice, pressures are often expressed in multiples of pascal:

• 1 kPa = 1,000 Pa
• 1 MPa = 1,000,000 Pa

What is a bar?

The bar is a non-SI unit of pressure widely used in engineering, meteorology, and industry. It was chosen to be close to atmospheric pressure at sea level:

• 1 bar = 100,000 Pa
• Standard atmosphere: 1 atm ≈ 1.01325 bar ≈ 101,325 Pa

Common multiples:

• millibar (mbar): 1 mbar = 0.001 bar = 100 Pa (often used in weather reports)
• bar: used for tire pressure, hydraulic systems, scuba diving, etc.

Bar to pascal reference values

The table below shows some commonly used conversions:

• 0.5 bar = 50,000 Pa = 50 kPa
• 1 bar = 100,000 Pa = 100 kPa = 0.1 MPa
• 2 bar = 200,000 Pa = 200 kPa = 0.2 MPa
• 5 bar = 500,000 Pa = 500 kPa = 0.5 MPa
• 10 bar = 1,000,000 Pa = 1,000 kPa = 1 MPa

FAQ: bar to pascal conversion

How do you convert bar to pascal?

Multiply the value in bar by 100,000. The relationship is exact: 1 bar = 100,000 Pa. Our calculator does this automatically as you type.

Is 1 bar exactly equal to 100,000 Pa?

Yes. By definition, 1 bar is exactly 100,000 pascals. There is no rounding in the conversion factor itself; any rounding only comes from how many decimal places you choose to display.

When should I use bar vs Pa, kPa, or MPa?

• Pa – very small pressures, theoretical work, or when strict SI units are required.
• kPa – engineering, HVAC, and many technical documents.
• MPa – high pressures, material strength, hydraulics.
• bar – industrial gauges, tire pressure, scuba, and legacy specifications.

Can I convert negative values?

Yes. Negative pressures can represent vacuum relative to a reference pressure. The conversion factor is linear, so negative values convert the same way: −1 bar = −100,000 Pa.