Conversion Amigo

Inches Of Mercury to Millimeters Of Mercury Converter

25.4

1 inHg = 25.4 mmHg

How to convert inches of mercury to millimeters of mercury

millimeters of mercury = inches of mercury × 25.4

To convert inches of mercury to millimeters of mercury, multiply the number of inches of mercury by 25.4.

1 inHg = 25.4 mmHg

Examples

  • Standard sea-level atmospheric pressure, as used for altimeter settings: 29.92 inHg × 25.4 = 759.968 mmHg
  • 30 inHg × 25.4 = 762 mmHg

Good to know

This is the conventional inch of mercury, about 3386.389 Pa. Values defined at a specific mercury temperature differ slightly, for example 3376.85 Pa at 60 °F.

This is the conventional millimeter of mercury, 133.322387415 Pa. It differs from the torr (101,325/760 Pa) by less than one part in seven million, so the two are interchangeable in practice.

Inches of mercury to millimeters of mercury conversion table

Inches of mercury (inHg) Millimeters of mercury (mmHg)
1 inHg 25.4 mmHg
5 inHg 127 mmHg
10 inHg 254 mmHg
20 inHg 508 mmHg
25 inHg 635 mmHg
28 inHg 711.2 mmHg
29 inHg 736.6 mmHg
29.5 inHg 749.3 mmHg
29.92 inHg 759.968 mmHg
30 inHg 762 mmHg
30.5 inHg 774.7 mmHg
31 inHg 787.4 mmHg
32 inHg 812.8 mmHg
35 inHg 889 mmHg

Unit definitions

Inch of mercury (inHg)
An inch of mercury is the pressure exerted by a 1 inch column of mercury, conventionally about 3386.389 pascals. It is used in the United States for barometric pressure in weather reports and aviation.
Millimeter of mercury (mmHg)
A millimeter of mercury is the pressure exerted by a 1 mm column of mercury, conventionally 133.322387415 pascals. It is the standard unit for blood pressure readings.

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