Atmosphere to Bar Converter
One Atmosphere equals 1.01325 Bar (1 atm = 1.01325 bar). Multiply a Atmosphere value by 1.01325 to get the equivalent in Bar. Use the calculator above for instant results, or follow the formula, worked examples, and reference table below.
Formula
bar = atm × 1.01325
Multiply the Atmosphere value by 1.01325 to get the equivalent value in Bar.
Example Conversions
1 Atmosphere (atm)
1.01325 Bar (bar)
5 Atmosphere (atm)
5.06625 Bar (bar)
10 Atmosphere (atm)
10.1325 Bar (bar)
25 Atmosphere (atm)
25.33125 Bar (bar)
100 Atmosphere (atm)
101.325 Bar (bar)
Conversion Table
| Atmosphere (atm) | Bar (bar) |
|---|---|
| 0.1 | 0.101325 |
| 0.5 | 0.506625 |
| 1 | 1.01325 |
| 2 | 2.0265 |
| 5 | 5.06625 |
| 10 | 10.1325 |
| 25 | 25.33125 |
| 50 | 50.6625 |
| 100 | 101.325 |
| 250 | 253.3125 |
| 500 | 506.625 |
| 1000 | 1013.25 |
How to Convert Manually
Use these steps to convert Atmosphere values to Bar without the calculator.
- Write down the value in Atmosphere (atm) that you want to convert.
- Multiply that value by 1.01325.
- For example, 10 Atmosphere × 1.01325 = 10.1325 Bar.
- Label the result as Bar (bar).
Relative Size Comparison
This chart shows the visual difference in size between exactly one Atmosphere and one Bar.
About Atmosphere and Bar
The standard atmosphere is defined as exactly 101,325 pascals — mean sea-level air pressure. Chemistry reference conditions and diving depth calculations use atmospheres. The bar is exactly 100,000 pascals, close to one atmosphere. European tire pressures, scuba tanks, and espresso machines are rated in bar. One Atmosphere equals 1.01325 Bar (1 atm = 1.01325 bar). Atmosphere to Bar conversion comes up most often in chemistry reference conditions and in diving depth pressure, typically when figures need restating for European tire pressures.
Precision and Rounding: Several pressure factors are exact by definition (1 atm = 101,325 Pa; 1 bar = 100,000 Pa) while others, like psi and mmHg, are derived and carry long decimals. Tire and weather readings tolerate whole-number rounding; calibration, medicine, and process engineering need the full factor before rounding.
Conversion factors per NIST Special Publication 811 and the BIPM SI Brochure (9th edition) (reference).
Worked Example
15 Atmosphere equals 15.19875 Bar.
15 atm × 1.01325 = 15.19875 bar
FAQ
How do I convert Atmosphere to Bar?
Multiply the Atmosphere value by 1.01325 to get the equivalent value in Bar.
What is the formula for Atmosphere to Bar?
The formula is bar = atm × 1.01325.
How many Bar are in 1 Atmosphere?
1 Atmosphere equals 1.01325 Bar.
Can I convert Bar back to Atmosphere?
Yes. 1 Bar equals 0.9869232667 Atmosphere, and the related converter can reverse the calculation.
What are common names for Atmosphere and Bar?
Atmosphere is shown as atm and may also be searched as atmospheres, standard atmosphere. Bar is shown as bar and may also be searched as bars.
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