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

inch of mercury
millimeter of water

›› More information from the unit converter

How many inch of mercury in 1 millimeter of water? The answer is 0.0028959020848759.
We assume you are converting between inch of mercury [0 C] and millimeter of water [4 C].
You can view more details on each measurement unit:
inch of mercury or millimeter of water
The SI derived unit for pressure is the pascal.
1 pascal is equal to 0.00029529983071445 inch of mercury, or 0.10197162129779 millimeter of 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 of water.
Type in your own numbers in the form to convert the units!

›› Quick conversion chart of inch of mercury to millimeter of water

1 inch of mercury to millimeter of water = 345.31554 millimeter of water

2 inch of mercury to millimeter of water = 690.63109 millimeter of water

3 inch of mercury to millimeter of water = 1035.94663 millimeter of water

4 inch of mercury to millimeter of water = 1381.26217 millimeter of water

5 inch of mercury to millimeter of water = 1726.57771 millimeter of water

6 inch of mercury to millimeter of water = 2071.89326 millimeter of water

7 inch of mercury to millimeter of water = 2417.2088 millimeter of water

8 inch of mercury to millimeter of water = 2762.52434 millimeter of water

9 inch of mercury to millimeter of water = 3107.83988 millimeter of water

10 inch of mercury to millimeter of water = 3453.15543 millimeter of water

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

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›› Common pressure conversions

inch of mercury to pound/square foot
inch of mercury to ton/square foot
inch of mercury to kilogram-force/square millimeter
inch of mercury to barye
inch of mercury to megapascal
inch of mercury to dyne/square centimeter
inch of mercury to kip/square foot
inch of mercury to water column
inch of mercury to kilopascal
inch of mercury to technical atmosphere

›› 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widely used for barometric pressure in weather reports and aviation in the United States, but is considered somewhat outdated elsewhere.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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ConvertUnits.com provides an online conversion calculator for all types of measurement units. You can find metric conversion tables for SI units, as well as English units, currency, and other data. Type in unit symbols, abbreviations, or full names for units of length, area, mass, pressure, and other types. Examples include mm, inch, 100 kg, US fluid ounce, 6'3", 10 stone 4, cubic cm, metres squared, grams, moles, feet per second, and many more!