How to convert atmospheres to bar
- Take the value in atmospheres.
- Use the formula bar = atmospheres × 1.01325.
- For example, 0.33 atm is 0.334 bar.
About atmospheres and bar
The standard atmosphere is defined as exactly 101,325 Pa, and the bar as exactly 100,000 Pa. So 1 atm is exactly 1.01325 bar: multiply atm by 1.01325 to get bar. For most purposes adding 1.3% is enough.
Atmospheres turn up in chemistry and physics problems, in older engineering references and in diving, where depth is often described in extra atmospheres. Gauges, regulators and spec sheets in Europe read in bar, so a value worked out in atm often needs converting before it can be compared.
Examples
- 0.33 atm (about a third of an atmosphere, near the summit of Everest) is 0.334 bar
- 1 atm (standard sea-level pressure) is 1.01 bar
- 2 atm (roughly the absolute pressure 10 m under the sea) is 2.03 bar
- 1,000 atm (roughly the pressure in the deepest ocean trenches) is 1,013.25 bar
Atmospheres to bar chart
| Atmospheres | Bar |
|---|---|
| 0.1 | 0.101 |
| 0.25 | 0.253 |
| 0.33 | 0.334 |
| 0.5 | 0.507 |
| 0.75 | 0.76 |
| 1 | 1.01 |
| 1.5 | 1.52 |
| 2 | 2.03 |
| 2.5 | 2.53 |
| 3 | 3.04 |
| 4 | 4.05 |
| 5 | 5.07 |
| Atmospheres | Bar |
|---|---|
| 6 | 6.08 |
| 8 | 8.11 |
| 10 | 10.13 |
| 15 | 15.2 |
| 20 | 20.27 |
| 25 | 25.33 |
| 50 | 50.66 |
| 100 | 101.33 |
| 200 | 202.65 |
| 500 | 506.63 |
| 1,000 | 1,013.25 |