›› Convert inch of mercury [0 C] to millimeter water [4 C]

millimeter water

›› More information from the unit converter

How many inHg in 1 millimeter water? The answer is 0.0028959020848759.
We assume you are converting between inch of mercury [0 C] and millimeter water [4 C].
You can view more details on each measurement unit:
inHg or millimeter water
The SI derived unit for pressure is the pascal.
1 pascal is equal to 0.00029529983071445 inHg, or 0.10197162129779 millimeter water.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between inches of mercury and millimeters water.
Type in your own numbers in the form to convert the units!

›› Quick conversion chart of inHg to millimeter water

1 inHg to millimeter water = 345.31554 millimeter water

2 inHg to millimeter water = 690.63109 millimeter water

3 inHg to millimeter water = 1035.94663 millimeter water

4 inHg to millimeter water = 1381.26217 millimeter water

5 inHg to millimeter water = 1726.57771 millimeter water

6 inHg to millimeter water = 2071.89326 millimeter water

7 inHg to millimeter water = 2417.2088 millimeter water

8 inHg to millimeter water = 2762.52434 millimeter water

9 inHg to millimeter water = 3107.83988 millimeter water

10 inHg to millimeter water = 3453.15543 millimeter water

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You can do the reverse unit conversion from millimeter water to inHg, or enter any two units below:

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›› Common pressure conversions

inHg to zeptopascal
inHg to decibar
inHg to centimeter of water
inHg to exapascal
inHg to attopascal
inHg to kilogram-force/square millimeter
inHg to pound/square inch
inHg to ton/square inch
inHg to inch of water
inHg to centimeter of mercury

›› Definition: Inch of mercury

Inches of mercury or inHg is a non-SI unit for pressure. It is still widely used for barometric pressure in weather reports and aviation in the United States, but is considered somewhat outdated elsewhere.

It is defined as the pressure exerted by a column of mercury of 1 inch in height at 32 F (0 C) at the standard acceleration of gravity.

1 inHg = 3,386.389 pascals at 0 C.

Aircraft operating at higher altitudes (above 18,000 feet) set their barometric altimeters to a standard pressure of 29.92 inHg or 1,013.2 hPa (1 hPa = 1 mbar) regardless of the actual sea level pressure, with inches of mercury used in the U.S. and Canada. The resulting altimeter readings are known as flight levels.

Piston engine aircraft with constant-speed propellers also use inHg to measure manifold pressure, which is indicative of engine power produced.

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