Millimeters Of Mercury to Inches Of Mercury
Convert millimeters of mercury to inches of mercury instantly — one millimeter of mercury is 0.0393701 inches of mercury.
| Millimeters Of Mercury | Inches Of Mercury |
|---|---|
| 1 mmHg | 0.03937 inHg |
| 2 mmHg | 0.07874 inHg |
| 3 mmHg | 0.11811 inHg |
| 5 mmHg | 0.19685 inHg |
| 10 mmHg | 0.393701 inHg |
| 25 mmHg | 0.984252 inHg |
| 50 mmHg | 1.968504 inHg |
| 100 mmHg | 3.937007 inHg |
How to use
- Enter a value in the Millimeters Of Mercury field.
- The Inches Of Mercury figure appears immediately — no button to press.
- Typing in the Inches Of Mercury field converts back to Millimeters Of Mercury the same way.
- Use the reference table for the values that come up most often.
Millimeters Of Mercury to Inches Of Mercury formula
The factor from millimeters of mercury to inches of mercury is 0.0393700746.
inHg = mmHg × 0.0393700746
Why this factor: the millimeter of mercury and the inch of mercury are both defined against the pascal, so dividing one definition by the other gives 0.0393700746 directly. Both definitions are set out in full below.
To go the other way, divide by 0.0393700746 — or use the Inches Of Mercury to Millimeters Of Mercury converter, which is the same calculation reversed.
Worked example
Given 760 mmHg, multiplying by 0.0393700746 yields 29.921257 inHg.
760 mmHg × 0.0393700746 = 29.921257 inHg
The converter above does this for any value you type, in either direction.
What is a millimeter of mercury?
A millimeter of mercury is the pressure exerted by a 1 mm column of mercury, still standard in medicine.
Definition: Defined as exactly 133.322387415 pascals.
Where it is used: Blood pressure readings, intraocular pressure, and respiratory gas pressures.
Worth knowing: Blood pressure is universally reported in mmHg even in fully metric countries — one of the most durable legacy units in medicine.
What is an inch of mercury?
An inch of mercury is the pressure of a one-inch mercury column, used for US barometric pressure.
Definition: About 3,386.389 pascals.
Where it is used: US weather barometric pressure, aircraft altimeter settings, and engine vacuum readings.
Millimeters Of Mercury vs Inches Of Mercury
The millimeter of mercury is a specialized unit while the inch of mercury is a US customary 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 inches of mercury are in a millimeter of mercury?
One millimeter of mercury equals 0.0393700746 inches of mercury.
What is the formula to convert millimeters of mercury to inches of mercury?
Multiply the number of millimeters of mercury by 0.0393700746. To reverse it, divide by 0.0393700746 instead.
How do I convert inches of mercury back to millimeters of mercury?
Divide by 0.0393700746, which is the same as multiplying by 25.4000027.
How many inches of mercury are in 10 millimeters of mercury?
10 mmHg works out to 0.393701 inHg.
Is there anything to watch out for with millimeters of mercury?
Blood pressure is universally reported in mmHg even in fully metric countries — one of the most durable legacy units in medicine.
How is the millimeter of mercury defined?
Defined as exactly 133.322387415 pascals.