Atmospheres to bar
Type a value in atmospheres to see it in bar straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the atmospheres box.
- Read the result in bar as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
bar = atm × 1.01325
Multiply the value in atmospheres by 1.01325 to get bar.
Example
To convert 25 atm to bar: 25 × 1.01325 = 25.3313 bar.
Conversion table
| Atmospheres (atm) | Bar (bar) |
|---|---|
| 1 | 1.01325 |
| 2 | 2.0265 |
| 3 | 3.03975 |
| 5 | 5.06625 |
| 10 | 10.1325 |
| 20 | 20.265 |
| 25 | 25.3313 |
| 50 | 50.6625 |
| 100 | 101.325 |
| 250 | 253.313 |
| 500 | 506.625 |
| 1,000 | 1,013.25 |
About the units
- Atmosphere
- The standard atmosphere, defined as exactly 101,325 pascals.
- Bar
- A metric unit equal to exactly 100,000 pascals, close to atmospheric pressure at sea level.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many bar are in one atmosphere?
1 atm = 1.01325 bar exactly.
How do I convert atmospheres to bar?
Use bar = atm × 1.01325. For example, 25 atm = 25.3313 bar.
How many atmospheres are in one bar?
1 bar = 0.986923 atm.
What is the difference between gauge and absolute pressure?
Gauge pressure is measured from the surrounding air pressure, while absolute pressure starts from a perfect vacuum. These converters change the unit only, so a gauge reading stays a gauge reading.
Are torr and mmHg the same?
Almost. One torr is 101325/760 Pa, about 133.322368 Pa, and one conventional mmHg is 133.322387 Pa, a difference of less than one part per million. For everyday use you can treat them as equal.