## ››Convert inch of mercury [0 °C] to attopascal

 inHg attopascal

How many inHg in 1 attopascal? The answer is 2.9529983071445E-22.
We assume you are converting between inch of mercury [0 °C] and attopascal.
You can view more details on each measurement unit:
inHg or attopascal
The SI derived unit for pressure is the pascal.
1 pascal is equal to 0.00029529983071445 inHg, or 1.0E+18 attopascal.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between inches of mercury and attopascals.
Type in your own numbers in the form to convert the units!

## ››Quick conversion chart of inHg to attopascal

1 inHg to attopascal = 3.3863886666667E+21 attopascal

2 inHg to attopascal = 6.7727773333333E+21 attopascal

3 inHg to attopascal = 1.0159166E+22 attopascal

4 inHg to attopascal = 1.3545554666667E+22 attopascal

5 inHg to attopascal = 1.6931943333333E+22 attopascal

6 inHg to attopascal = 2.0318332E+22 attopascal

7 inHg to attopascal = 2.3704720666667E+22 attopascal

8 inHg to attopascal = 2.7091109333333E+22 attopascal

9 inHg to attopascal = 3.0477498E+22 attopascal

10 inHg to attopascal = 3.3863886666667E+22 attopascal

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

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widely used for barometric pressure in weather reports and aviation in the United States, but is considered somewhat outdated elsewhere.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

## ››Definition: Attopascal

The SI prefix "atto" represents a factor of 10-18, or in exponential notation, 1E-18.

So 1 attopascal = 10-18 pascals.

The definition of a pascal is as follows:

The pascal (symbol Pa) is the SI unit of pressure.It is equivalent to one newton per square metre. The unit is named after Blaise Pascal, the eminent French mathematician, physicist and philosopher.

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