Inches Of Mercury to Psi
Convert inches of mercury to psi instantly — one inch of mercury is 0.491154 psi.
| Inches Of Mercury | Psi |
|---|---|
| 1 inHg | 0.491154 psi |
| 2 inHg | 0.982308 psi |
| 3 inHg | 1.473463 psi |
| 5 inHg | 2.455771 psi |
| 10 inHg | 4.911542 psi |
| 25 inHg | 12.278855 psi |
| 50 inHg | 24.55771 psi |
| 100 inHg | 49.11542 psi |
How to use
- Enter a value in the Inches Of Mercury field.
- The Psi figure appears immediately — no button to press.
- Typing in the Psi field converts back to Inches Of Mercury the same way.
- Use the reference table for the values that come up most often.
Inches Of Mercury to Psi formula
The factor from inches of mercury to psi is 0.4911542.
psi = inHg × 0.4911542
Why this factor: the inch of mercury and the pound per square inch are both defined against the pascal, so dividing one definition by the other gives 0.4911542 directly. Both definitions are set out in full below.
To go the other way, divide by 0.4911542 — or use the Psi to Inches Of Mercury converter, which is the same calculation reversed.
Worked example
Start with 100 inHg. Multiply by 0.4911542 to get 49.11542 psi.
100 inHg × 0.4911542 = 49.11542 psi
The converter above does this for any value you type, in either direction.
What is an inch of mercury?
An inch of mercury is the pressure of a one-inch mercury column, used for US barometric pressure.
Definition: About 3,386.389 pascals.
Where it is used: US weather barometric pressure, aircraft altimeter settings, and engine vacuum readings.
What is a pound per square inch?
Pounds per square inch is the standard pressure unit in the United States.
Definition: One pound-force per square inch, which is about 6,894.757 pascals.
Where it is used: US tire pressure, compressed air and hydraulic systems, and plumbing water pressure.
Inches Of Mercury vs Psi
The inch of mercury and the pound per square inch belong to the same family of units, so converting between them is usually a matter of shifting a decimal point or applying a small whole-number factor.
Frequently asked questions
How many psi are in an inch of mercury?
One inch of mercury equals 0.4911542 psi.
What is the formula to convert inches of mercury to psi?
Multiply the number of inches of mercury by 0.4911542. To reverse it, divide by 0.4911542 instead.
How do I convert psi back to inches of mercury?
Divide by 0.4911542, which is the same as multiplying by 2.03602046.
How many psi are in 10 inches of mercury?
10 inHg works out to 4.911542 psi.
How is the inch of mercury defined?
About 3,386.389 pascals.