Bars to Atmospheres
An instant bars-to-atmospheres converter, with the formula and a reference table below.
| Bars | Atmospheres |
|---|---|
| 1 bar | 0.986923 atm |
| 2 bar | 1.973847 atm |
| 3 bar | 2.96077 atm |
| 5 bar | 4.934616 atm |
| 10 bar | 9.869233 atm |
| 25 bar | 24.673082 atm |
| 50 bar | 49.346163 atm |
| 100 bar | 98.692327 atm |
How to use
- Enter a value in the Bars field.
- The Atmospheres figure appears immediately — no button to press.
- Typing in the Atmospheres field converts back to Bars the same way.
- Use the reference table for the values that come up most often.
Bars to Atmospheres formula
To convert bars to atmospheres, multiply by 0.986923267.
atm = bar × 0.986923267
Why this factor: the bar and the atmosphere are both defined against the pascal, so dividing one definition by the other gives 0.986923267 directly. Both definitions are set out in full below.
To go the other way, divide by 0.986923267 — or use the Atmospheres to Bars converter, which is the same calculation reversed.
Worked example
Given 32 bar, multiplying by 0.986923267 yields 31.581545 atm.
32 bar × 0.986923267 = 31.581545 atm
The converter above does this for any value you type, in either direction.
What is a bar?
A bar is a metric pressure unit chosen to sit very close to atmospheric pressure.
Definition: Exactly 100,000 pascals by definition. Standard atmosphere is 1.01325 bar, so a bar is slightly less.
Where it is used: European tire and hydraulic pressures, diving depth equivalents, and espresso machine ratings.
Worth knowing: Close to one atmosphere but not equal to it — the difference is about 1.3%.
What is an atmosphere?
A standard atmosphere is a fixed reference pressure, originally average sea-level air pressure.
Definition: Defined as exactly 101,325 pascals — an exact convention, not a measurement.
Where it is used: Chemistry reference conditions, diving pressure, and high-pressure physics.
Bars vs Atmospheres
The bar is a metric unit while the atmosphere is a specialized unit. That is why the factor between them is not a round number: the two systems were defined independently and only later tied together by exact agreement.
Frequently asked questions
How many atmospheres are in a bar?
One bar equals 0.986923267 atmospheres.
What is the formula to convert bars to atmospheres?
Multiply the number of bars by 0.986923267. To reverse it, divide by 0.986923267 instead.
How do I convert atmospheres back to bars?
Divide by 0.986923267, which is the same as multiplying by 1.01325.
How many atmospheres are in 10 bars?
10 bar works out to 9.869233 atm.
Is there anything to watch out for with bars?
Close to one atmosphere but not equal to it — the difference is about 1.3%.
How is the bar defined?
Exactly 100,000 pascals by definition. Standard atmosphere is 1.01325 bar, so a bar is slightly less.