MmHg to Atmospheres Converter
Convert mmHg to atmospheres instantly. 1 mmHg = 0.001316 atm. Free two-way converter with the formula and a quick reference table.
How to convert mmHg to atmospheres
atmospheres = mmHg × 0.001316
One millimeter of mercury equals 0.001316 atmospheres, so to convert mmHg to atmospheres you multiply by 0.001316. Going the other way, one atmosphere is 760 mmHg. Both units measure pressure, so the conversion is an exact ratio that never changes.
10 mmHg = 0.013158 atmospheres. Multiply your millimeter of mercury figure by the factor above (or just type it into the box) to convert any amount.
mmHg to atmospheres table
| mmHg (mmHg) | atmospheres (atm) |
|---|---|
| 1 | 0.001316 |
| 2 | 0.002632 |
| 3 | 0.003947 |
| 5 | 0.006579 |
| 10 | 0.013158 |
| 20 | 0.026316 |
| 25 | 0.032895 |
| 50 | 0.065789 |
| 100 | 0.131579 |
| 250 | 0.328947 |
| 500 | 0.657895 |
| 1,000 | 1.3158 |
Frequently asked questions
How many atmospheres are in a millimeter of mercury?
One millimeter of mercury equals 0.001316 atmospheres. So to convert, multiply the number of mmHg by 0.001316.
How do I convert mmHg to atmospheres?
Multiply by 0.001316, or simply enter the value in the converter above — it does the math instantly and works both ways.
Is this conversion exact?
Yes — both units measure the same quantity, so the ratio is fixed and this uses the standard internationally-agreed factor.