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Bar to Pascals Converter
↔ Convert Pa to bar instead

Common Conversions

bar Pa
0.001 100
0.01 1000
0.1 10000
0.5 50000
1 100000
1.01325 101325
2 200000
5 500000
10 1000000
100 10000000
200 20000000

Why this conversion matters in chemistry

Bar is what most modern chemistry data uses for pressure — it's IUPAC's reference for tabulated thermodynamic standard states, and the numbers come out tidy. The pascal is the SI base unit, but at atmospheric scale it gets unwieldy: 1 bar is 100,000 Pa, and a high-pressure synthesis at 200 bar lives at 20 MPa or 2 × 10⁷ Pa. The conversion is exact through the bar's definition, so the only thing it changes is the size of the exponent. The arithmetic earns its keep mostly when an equation written in pure SI — Navier-Stokes, Bernoulli, anything with R in J/(mol·K) — needs the pressure in pascals to make the rest of the units cancel.

Formula

Pa = bar × 100000

Worked Examples

1 bar = 100000 Pa

The defining identity — 1 bar is exactly 10⁵ Pa by construction.

1.01325 bar = 101325 Pa

One standard atmosphere expressed in pascals — the value any sea-level gas-law calculation in pure SI starts from.

0.01 bar = 1000 Pa

A low vacuum, the kind a rotary-vane pump pulls when bringing a Schlenk line to working pressure.

200 bar = 20000000 Pa

The pressure inside a full compressed-gas cylinder, also written as 20 MPa in process documentation.

Frequently Asked Questions

How do I convert bar to Pa?
Multiply by 100,000. The relationship is exact, so 1 bar is precisely 100,000 Pa with no rounding.
Is bar to Pa an exact conversion?
Yes. The bar is defined as exactly 10⁵ pascals — that's the construction of the unit, not a measured ratio. The conversion introduces no uncertainty.
When does the calculation want pressure in Pa instead of bar?
Whenever R = 8.314 J/(mol·K) is in play. PV = nRT gives an energy in joules only when P is in Pa and V is in m³. Mixing R in J/(mol·K) with P in bar quietly drops a factor of 10⁵ from the answer.
How does bar relate to megapascals?
1 bar = 0.1 MPa, so 10 bar is 1 MPa and 100 bar is 10 MPa. The MPa scale is convenient for high-pressure work — supercritical fluids, hydrogenation reactors, geochemistry — where atmospheric-scale numbers would have too many trailing zeros.