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Single conversion
To convert from millimeter of mercury (mmHg) to pascal (Pa), use the following formula:
Let's convert 5 millimeter of mercury (mmHg) to pascal (Pa).
Using the formula:
Therefore, 5 millimeter of mercury (mmHg) is equal to pascal (Pa).
Here are some quick reference conversions from millimeter of mercury (mmHg) to pascal (Pa):
| millimeters of mercury | pascals |
|---|---|
| 0.000001 mmHg | Pa |
| 0.001 mmHg | Pa |
| 0.1 mmHg | Pa |
| 1 mmHg | Pa |
| 2 mmHg | Pa |
| 3 mmHg | Pa |
| 4 mmHg | Pa |
| 5 mmHg | Pa |
| 6 mmHg | Pa |
| 7 mmHg | Pa |
| 8 mmHg | Pa |
| 9 mmHg | Pa |
| 10 mmHg | Pa |
| 20 mmHg | Pa |
| 30 mmHg | Pa |
| 40 mmHg | Pa |
| 50 mmHg | Pa |
| 100 mmHg | Pa |
| 1000 mmHg | Pa |
| 10000 mmHg | Pa |
For all Pressure converters, choose units using the From/To dropdowns above.
A millimeter of mercury (mmHg) is a manometric unit of pressure.
It was historically defined as the pressure generated by a column of mercury exactly one millimeter high.
Today, it is most famous as the unit used in medicine for measuring blood pressure. It is also commonly used in meteorology, aviation, and physics to measure atmospheric pressure or vacuum pressure.
The mmHg unit originates from the invention of the barometer by Evangelista Torricelli in 1643.
Torricelli's device measured atmospheric pressure by seeing how high it could support a column of mercury in a tube.
Standard atmospheric pressure was found to support a column approximately 760 mm high, which established 760 mmHg as a standard reference point.
The most well-known application of mmHg is in medicine.
Blood Pressure: Readings are given as two numbers: systolic pressure (when the heart beats) over diastolic pressure (when the heart rests), such as 120/80 mmHg. This is a critical vital sign for human health.
Meteorology: Used for reporting barometric (atmospheric) pressure, which helps in weather forecasting.
Physics & Engineering: Used for measuring vacuum pressures and other low-pressure systems where precision is needed.
While mmHg is common, other pressure units are standard in different fields. Here are the most common conversions:
A pascal (Pa) is the standard unit of pressure in the International System of Units (SI). It is a derived unit, meaning other base units define it.
The primary pascal definition is one newton of force applied over an area of one square meter (1 Pa = 1 N/m2).
Because a single pascal represents a very small amount of pressure, it is most often seen in multiples.
The most common multiples are the kilopascal (kPa), equal to 1,000 pascals, and the megapascal (MPa), equal to 1,000,000 pascals.
These units are widely used in fields from weather forecasting to material science.
The pascal (Pa) unit is named in honor of Blaise Pascal, a key 17th-century French mathematician, physicist, and inventor.
His groundbreaking work on how fluids behave under pressure (known as hydrodynamics and hydrostatics) and his formulation of Pascal's Law were essential to our modern understanding of pressure.
To understand just how small a single pascal is, here are two real-world examples:
This shows why, for most everyday measurements (like tire pressure or weather), the larger kilopascal (kPa) is much more practical.