Pressure is everywhere, and we measure it in many different ways! From tire inflation to weather reports, various fields use different units to describe pressure.
This article explains how to convert between two common pressure units: pounds per square inch (psi) and millimeters of mercury (mmHg). So, if you’re looking to convert from psi to mm Hg, read on!
Understanding PSI and mmHg
Before diving into the conversion, let’s define the terms.
What is Pounds per Square Inch (PSI)?
PSI is a unit of measurement for pressure. It stands for pounds per square inch and measures the amount of force, in pounds, exerted on a one-inch square.
You’ll often see PSI used to measure tire pressure or in various industrial applications.
What is Millimeters of Mercury (mmHg)?
Millimeters of mercury, or mmHg, is another unit of pressure. It’s a manometric unit that was originally based on how high a column of mercury would rise under a certain amount of pressure.
You’ll most often see mmHg used to measure blood pressure or in meteorology.
The Conversion Formula
Here’s how to convert between these two units:
- To convert millimeters of mercury (mmHg) to pounds per square inch (psi), use this formula: psi = mmHg ÷ 51.71493256
- To convert pounds per square inch (psi) to millimeters of mercury (mmHg), use this formula: mmHg = psi 51.7150754803
These conversion factors are based on the established relationships between these units under standard conditions.
Examples: Converting between mmHg and psi
Let’s walk through a couple of examples to show how these conversions work.
Example 1: Convert 975 mmHg to psi
To convert from mmHg to psi, divide by 51.71493256:
975 mmHg ÷ 51.71493256 = 18.8533553 psi.
Example 2: Convert 15 psi to mmHg
To convert from psi to mmHg, multiply by 51.7150754803:
15 psi 51.7150754803 = 775.7261322 mmHg.
Conversion Tables
Here are a couple of quick conversion charts to help you switch between mmHg and psi:
mmHg to Psi
| mmHg | psi |
|---|---|
| 1 mmHg | 0.0193368 psi |
| 100 mmHg | 1.9336775 psi |
| 500 mmHg | 9.6683876 psi |
| 760 mmHg | 14.6959 psi |
Psi to mmHg (0°C)
| psi | mmHg |
|---|---|
| 1 psi | 51.7150754803 mmHg |
| 10 psi | 517.150754803 mmHg |
| 25 psi | 1292.87688701 mmHg |
Key Takeaways
Knowing how to convert between psi and mmHg is essential in science and engineering.
Whether you’re using the formulas or looking at a conversion table, be sure to convert accurately. It could make all the difference in your work!