Inches of mercury (inHg) to Pounds per square inch (psi) Conversion
Inches of mercury
The inch of mercury (inHg) is a unit of pressure equal to the pressure exerted by a column of mercury 1 inch (25.4 mm) high — approximately 3,386.39 Pa or 0.0334 atm. It is used in US aviation for altimeter settings (standard pressure is 29.92 inHg) and in US weather reports for barometric pressure. Pilots set their altimeters in inHg based on local barometric pressure to ensure accurate altitude readings.
Pounds per square inch
Pounds per square inch (psi) is a unit of pressure defined as one pound-force per square inch (approximately 6,894.76 Pa). It is the standard for tyre pressure, hydraulic systems, and gas cylinders in the United States. Standard atmospheric pressure is approximately 14.696 psi. In engineering, gauge pressure (psig — relative to atmosphere) is distinguished from absolute pressure (psia — relative to a perfect vacuum), a distinction critical in thermodynamics and fluid system design.
| Inches of mercury (inHg) | Pounds per square inch (psi) |
|---|---|
| 0.1 inHg | 0.0491 psi |
| 1 inHg | 0.4912 psi |
| 2 inHg | 0.9823 psi |
| 3 inHg | 1.4735 psi |
| 5 inHg | 2.4558 psi |
| 10 inHg | 4.9115 psi |
| 20 inHg | 9.8231 psi |
| 30 inHg | 14.7346 psi |
| 50 inHg | 24.5577 psi |
| 100 inHg | 49.1154 psi |
| 1000 inHg | 491.1541 psi |
Frequently Asked Questions (FAQ)
How many pounds per square inch are in 1 inches of mercury?
1 inches of mercury (inHg) is exactly 0.491154 pounds per square inch (psi).
How do I convert inches of mercury to pounds per square inch?
Multiply the value in inches of mercury by 0.491154 to get the result in pounds per square inch. Or use the converter above — type any number and see the result instantly.