Why Convert Millimeters of Mercury to PSI?
Converting between millimeters of mercury (mmHg) and psi (psi) is one of the most common pressure conversions. Whether for engineering, cooking, travel, or science, knowing how to quickly convert mmHg to psi saves time and prevents errors.
Pressure conversions between mmHg and psi are vital in automotive maintenance, meteorology, and scuba diving. Tire pressure affects fuel efficiency and safety, requiring drivers to convert between PSI and bar depending on the gauge used. Divers must strictly monitor pressure to avoid decompression sickness, often needing to convert depth and tank pressure readings. In weather forecasting, atmospheric pressure changes indicate approaching storms, with data often shared in different units globally. Failing to convert pressure accurately can lead to equipment failure, tire blowouts, or life-threatening situations underwater.
How to Convert Millimeters of Mercury to PSI
To convert millimeters of mercury to psi, use the following formula:
psi = mmHg × 0.01933677746
Example: 1 mmHg = 0.01933677746 psi
For example, 5 mmHg = 0.0966838873 psi, 10 mmHg = 0.1933677746 psi, and 100 mmHg = 1.933677746 psi. For larger values, 1000 mmHg = 19.33677746 psi. Conversely, 1 psi = 51.7149252 mmHg. Our calculator above performs this conversion instantly with full precision — no rounding errors.
Common Mistakes to Avoid
- Gauge vs Absolute: confusing gauge pressure (psig) with absolute pressure (psia).
- Bar vs Pascal: 1 Bar is 100,000 Pascals, not 10 or 100.
- Atmosphere variations: confusing standard atm with technical atm.
Pro Tips
- Tire checks: Check tire pressure when cold (tires heat up and pressure rises while driving).
- PSI rule: Typical car tires are 30-35 PSI.
- Altitude effect: Air pressure drops as you go higher (ears popping).
What is a Millimeter of Mercury?
Millimeter of mercury.
Blood pressure and vacuum systems.
What is a PSI?
PSI (Pounds per Square Inch) is a unit of pressure in the Imperial and US customary systems. It represents the force of one pound-force applied to an area of one square inch.
PSI is the standard unit for tire pressure, industrial hydraulics, and compressed gas systems in the United States and UK.