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

millimeter of water

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How many millimeter of water in 1 inHg? The answer is 345.31554268447.
We assume you are converting between millimeter of water [4 C] and inch of mercury [0 C].
You can view more details on each measurement unit:
millimeter of water or inHg
The SI derived unit for pressure is the pascal.
1 pascal is equal to 0.10197162129779 millimeter of water, or 0.00029529983071445 inHg.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between millimeters of water and inches of mercury.
Type in your own numbers in the form to convert the units!

›› Quick conversion chart of millimeter of water to inHg

1 millimeter of water to inHg = 0.0029 inHg

10 millimeter of water to inHg = 0.02896 inHg

50 millimeter of water to inHg = 0.1448 inHg

100 millimeter of water to inHg = 0.28959 inHg

200 millimeter of water to inHg = 0.57918 inHg

500 millimeter of water to inHg = 1.44795 inHg

1000 millimeter of water to inHg = 2.8959 inHg

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

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›› Common pressure conversions

millimeter of water to gigapascal
millimeter of water to millihg
millimeter of water to nanobar
millimeter of water to decibar
millimeter of water to kilopascal
millimeter of water to attopascal
millimeter of water to ton/square meter
millimeter of water to centipascal
millimeter of water to foot mercury
millimeter of water to kilopond/square meter

›› 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widely used for barometric pressure in weather reports and aviation in the United States, but is considered somewhat outdated elsewhere.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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