How many psi are in 1 mmhg?

1 mmhg equals 0.0193367775 psi, using the exact defined conversion factor rather than an estimate.

How do I convert mmhg to psi?

Multiply the mmhg value by 0.01933677746. The converter above does this instantly to whatever precision you set.

How do I convert psi back to mmhg?

Use the reverse factor: 1 psi equals 51.7149252 mmhgs. You can also use the swap control in the converter above to flip the direction instantly.

mmHg (mmHg) is a unit of engineering.

Is the mmhg to psi conversion exact?

Yes. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.

Why do engineering unit conventions vary so much by region and industry?

Pressure, force, and stress can be expressed in metric (pascal, newton), US customary (psi, pound-force), or older and industry-specific units (atmosphere, torr, kip) depending on the country, industry, and even the equipment manufacturer, which is why engineers routinely need to convert between them when working across specs from different sources.

mmHgs to PSI Converter

Q: What is a psi?

PSI (psi) measures pressure. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. It is classified as a US/imperial customary unit.

About Converting mmHgs to PSI

mmHg and PSI both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. Specifically: Millimeters of mercury at standard gravity, and pounds per square inch.

Formula

psi = mmhgs × 0.0193367774595

This factor comes from each unit's defined relationship to the category's base unit: 1 mmhg equals 133.322387415 base units, and 1 psi equals 6894.75729317 base units, so dividing one by the other gives the direct mmhg-to-psi factor of 0.0193367774595.

Simple example

1 mmHg × 0.01933677746 = 0.0193367775 psi

1 mmhg = 0.0193367775 psi.

Real-world example

100 mmHg × 0.01933677746 = 1.933677746 psi

100 mmhgs = 1.933677746 psi.

Conversion table

mmHg (mmHg)	PSI (psi)
1 mmHg	0.0193367775 psi
10 mmHg	0.1933677746 psi
50 mmHg	0.966838873 psi
100 mmHg	1.933677746 psi
500 mmHg	9.66838873 psi
1,000 mmHg	19.33677746 psi

Reverse conversion: PSI to mmHg

0.0193367775 psi × 51.7149252 = 1.000000002 mmHg

0.0193367775 psi = 1.000000002 mmhgs.

mmhgs = psi × 51.7149252039

For a page dedicated to this direction, see PSI to mmHg.

Understanding the mmHg (mmHg)

Millimeters of mercury at standard gravity.

Understanding the PSI

PSI (psi) measures pressure. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. It is classified as a US/imperial customary unit.

Where it's used: United States (standard pressure unit for tires, tools, and plumbing)

Uses of the PSI today

Tire pressure specifications in the US
Hydraulic and pneumatic system ratings
Plumbing, compressed-air tools, and industrial equipment ratings

History of the PSI

PSI is a derived unit from the pound-force and the inch, both themselves standardized through English and later international agreements rather than invented as a pressure unit from scratch.

It became the default pressure unit in US engineering as pound-force and inch-based measurement dominated American industry through the 19th and 20th centuries, and it remains in everyday use for tires and tools even as most other measurements in the US context stay imperial.

Historical origin. PSI was not the invention of a single named person; it developed through the process described above.

PSI — sources

NIST Special Publication 811 — Guide for the Use of the International System of Units — Documents conversion factors for psi and other US customary pressure units.

mmHgs to PSI Converter — mmHg to psi

Engineering Converter