›› Convert millimeter water [4 °C] to inch of water [4 °C]

mm H2O
inch of water

›› More information from the unit converter

How many mm H2O in 1 inch of water? The answer is 25.399999830047.
We assume you are converting between millimeter water [4 °C] and inch of water [4 °C].
You can view more details on each measurement unit:
mm H2O or inch of water
The SI derived unit for pressure is the pascal.
1 pascal is equal to 0.10197162129779 mm H2O, or 0.0040146307866177 inch of water.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between millimeters water and inches of water.
Type in your own numbers in the form to convert the units!

›› Quick conversion chart of mm H2O to inch of water

1 mm H2O to inch of water = 0.03937 inch of water

10 mm H2O to inch of water = 0.3937 inch of water

20 mm H2O to inch of water = 0.7874 inch of water

30 mm H2O to inch of water = 1.1811 inch of water

40 mm H2O to inch of water = 1.5748 inch of water

50 mm H2O to inch of water = 1.9685 inch of water

100 mm H2O to inch of water = 3.93701 inch of water

200 mm H2O to inch of water = 7.87402 inch of water

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You can do the reverse unit conversion from inch of water to mm H2O, or enter any two units below:

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›› Common pressure conversions

mm H2O to gram/square centimeter
mm H2O to inch of mercury
mm H2O to gigapascal
mm H2O to inch water column
mm H2O to kilonewton/square meter
mm H2O to centimeter mercury
mm H2O to water column
mm H2O to femtopascal
mm H2O to dekapascal
mm H2O to pound/square inch

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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!