Convert atmospheres to millimeters of mercury
Converting atmospheres to millimeters of mercury is a common pressure task, whether you are checking a recipe, a spec sheet, a travel distance or a homework problem. Since 1 atm equals 760 mmHg, the math is a single multiplication — and this page does it for you instantly, with the formula, a table of common values and answers to the questions people ask most.
Exact factor
How to convert atmospheres to millimeters of mercury
To convert atmospheres to millimeters of mercury, multiply the number of atmospheres by 760. For example, 10 atm × 760 = 7,600 mmHg.
mmHg = atm × 760
- Write down the value in atmospheres you want to convert.
- Multiply it by 760 (the exact atm→mmHg factor).
- The result is your value in millimeters of mercury. Check it below with the converter or the table.
Conversion table
Common values of atmospheres and their equivalents in millimeters of mercury:
| atm | mmHg |
|---|---|
| 1 | 760 |
| 2 | 1,520 |
| 3 | 2,280 |
| 4 | 3,040 |
| 5 | 3,800 |
| 10 | 7,600 |
| 20 | 15,200 |
| 25 | 19,000 |
| 50 | 38,000 |
| 100 | 76,000 |
| 250 | 190,000 |
| 500 | 380,000 |
About these units
Atmosphere (atm). One standard atmosphere is defined as exactly 101,325 pascals, the reference average pressure of Earth's atmosphere at sea level. It anchors chemistry and gas-law calculations.
Millimeter of Mercury (mmHg). A millimeter of mercury is the pressure exerted by a one-millimeter column of mercury, about 133.32 pascals. Blood pressure and vacuum measurements are still quoted in mmHg.
Frequently asked questions
How do I convert atmospheres to millimeters of mercury?
To convert atmospheres to millimeters of mercury, multiply the number of atmospheres by 760. For example, 10 atm × 760 = 7,600 mmHg. Or skip the math: type the value into the converter at the top of this page and the result updates instantly.
How many millimeters of mercury are in 1 atmosphere?
1 atm = 760 mmHg. That is the fixed relationship used by this converter and by international standards.
How many atmospheres are in 1 millimeter of mercury?
1 mmHg = 0.00131579 atm. If you are converting in the opposite direction, use our Millimeter of Mercury to Atmosphere converter for the dedicated table and FAQ.
Is the atmospheres to millimeters of mercury conversion exact?
Yes. Both units are defined by international agreement, so the factor of 760 is exact. Displayed results are rounded to 6 significant digits only for readability.
What is atmosphere used for?
One standard atmosphere is defined as exactly 101,325 pascals, the reference average pressure of Earth's atmosphere at sea level. It anchors chemistry and gas-law calculations.