›› Convert millimeter water [4 °C] to pound/square inch

mm H2O
pound/square inch

The above form works if you are measuring differential pressure, such as the difference in psi between two points. It also gives the correct answer for absolute pressure, assuming you are measuring psia, which is the pressure relative to absolute zero vacuum.

If you are measuring relative to vacuum and want to resolve the pressure relative to the atmosphere, then you should use the form below.

mm H2O (relative to vacuum)
pound/square inch (relative to atmosphere)

Did you mean to convert mm H2O to pound/square inch
pound/square inch [gauge]
pound/square inch [absolute]

›› More information from the unit converter

How many mm H2O in 1 pound/square inch? The answer is 703.06957829636.
We assume you are converting between millimeter water [4 °C] and pound/square inch.
You can view more details on each measurement unit:
mm H2O or pound/square inch
The SI derived unit for pressure is the pascal.
1 pascal is equal to 0.10197162129779 mm H2O, or 0.00014503773800722 pound/square inch.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between millimeters water and pounds/square inch.
Type in your own numbers in the form to convert the units!

›› Quick conversion chart of mm H2O to pound/square inch

1 mm H2O to pound/square inch = 0.00142 pound/square inch

10 mm H2O to pound/square inch = 0.01422 pound/square inch

50 mm H2O to pound/square inch = 0.07112 pound/square inch

100 mm H2O to pound/square inch = 0.14223 pound/square inch

200 mm H2O to pound/square inch = 0.28447 pound/square inch

500 mm H2O to pound/square inch = 0.71117 pound/square inch

1000 mm H2O to pound/square inch = 1.42233 pound/square inch

›› Want other units?

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

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›› Common pressure conversions

mm H2O to micron of mercury
mm H2O to kilonewton/square meter
mm H2O to centitorr
mm H2O to inch of water
mm H2O to yottapascal
mm H2O to bar
mm H2O to nanobar
mm H2O to foot of mercury
mm H2O to millihg
mm H2O to kilopond/square millimeter

›› Definition: Pound/square inch

The pound per square inch or, more accurately, pound-force per square inch (symbol: psi or lbf/inē or lbf/inē) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an area of one 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!