Atmospheres to Millibars Converter
Convert atmospheres (atm) to millibars (mbar) instantly. Pressure conversions are used for tyre pressure (psi or bar), blood pressure readings in mmHg and weather maps in millibars.
Result
- Millibars
- 1,013.25 mbar
How to use the atmospheres to millibars converter
- Enter the atmospheres (atm).
- The results update as you type, or press Calculate.
- Read the millibars first, then the supporting figures below it.
Formula
Millibars = atmospheres × 1,013.25
Worked example
For example, with these inputs:
- Atmospheres (atm): 1
the calculator returns:
- Millibars: 1,013.25 mbar
Atmospheres to Millibars table
| Atmospheres | Millibars |
|---|---|
| 1 atm | 1,013.25 mbar |
| 2 atm | 2,026.5 mbar |
| 5 atm | 5,066.25 mbar |
| 10 atm | 10,132.5 mbar |
| 20 atm | 20,265 mbar |
| 25 atm | 25,331.25 mbar |
| 50 atm | 50,662.5 mbar |
| 100 atm | 101,325 mbar |
| 250 atm | 253,312.5 mbar |
| 500 atm | 506,625 mbar |
| 1,000 atm | 1,013,250 mbar |
About this conversion
Pressure conversions are used for tyre pressure (psi or bar), blood pressure readings in mmHg and weather maps in millibars.
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.
Frequently asked questions
How many millibars are in one atmosphere?
1 atm = 1,013.25 mbar.
How do I convert atm to mbar?
Millibars = atmospheres × 1,013.25.