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Single conversion
To convert from Inch of mercury (inHg) to torr (torr), use the following formula:
With is the ratio between the base units kilopascal (kPa) and kilopound per square inch (ksi).
Let's convert 5 Inch of mercury (inHg) to torr (torr).
Using the formula:
Therefore, 5 Inch of mercury (inHg) is equal to torr (torr).
Here are some quick reference conversions from Inch of mercury (inHg) to torr (torr):
| Inches of mercury | torr |
|---|---|
| 0.000001 inHg | torr |
| 0.001 inHg | torr |
| 0.1 inHg | torr |
| 1 inHg | torr |
| 2 inHg | torr |
| 3 inHg | torr |
| 4 inHg | torr |
| 5 inHg | torr |
| 6 inHg | torr |
| 7 inHg | torr |
| 8 inHg | torr |
| 9 inHg | torr |
| 10 inHg | torr |
| 20 inHg | torr |
| 30 inHg | torr |
| 40 inHg | torr |
| 50 inHg | torr |
| 100 inHg | torr |
| 1000 inHg | torr |
| 10000 inHg | torr |
For all Pressure converters, choose units using the From/To dropdowns above.
An inch of mercury, often abbreviated as inHg, is a unit of pressure.
It is not part of the standard metric (SI) system but is widely used in the United States and in specific fields like meteorology and aviation.
The unit is defined by its name: it is the amount of pressure exerted by a column of liquid mercury exactly one inch tall at a standard temperature.
You will most commonly encounter inches of mercury in a few key areas:
Weather Reporting: In the U.S., inHg is the standard unit for reporting barometric pressure (also known as atmospheric pressure).
A "high" pressure system indicating clear weather might be around 30.50 inHg, while a "low" pressure system associated with storms could be 28.50 inHg.
Aviation: This measurement is critical for pilot safety.
Pilots use the local barometric pressure (in inHg) to calibrate their altimeters—instruments that measure altitude—to ensure they are flying at the correct height.
Vacuum Systems: The unit is also widely used in science and industry to measure vacuum pressure.
This is common in systems like air conditioning, refrigeration, and for monitoring the manifold pressure in piston engines.
Because inHg is not a global standard, it's often necessary to convert it to other pressure units for calculations or international use.
Here are the most common conversions for 1 inHg:
A torr (Torr) is a unit of pressure.
It is primarily used to measure a vacuum, or pressures much lower than the air pressure we experience every day.
While the modern standard (SI) unit for pressure is the pascal (Pa), the torr is still widely used in many scientific and engineering fields.
For conversion, one torr is equal to about 133.32 pascals.
A much simpler way to think about it is in relation to our atmosphere: one standard atmosphere (atm) is defined as exactly 760 Torr.
The unit is named in honor of Evangelista Torricelli, the 17th-century Italian physicist who invented the mercury barometer.
Because of this, one torr was initially defined as being equal to one millimeter of mercury (mmHg).
This means 1 Torr is the pressure exerted by a column of mercury that is one millimeter high.
As mentioned, the torr's most convenient relationship is with the standard atmosphere (atm).
One standard atmosphere—the average air pressure at sea level—is set at exactly 760 Torr.
This straightforward, whole-number conversion makes the torr a popular choice for anyone working with fractions of atmospheric pressure.
The torr is the primary unit of measurement for high-vacuum and ultra-high-vacuum technology.
Because it is such a small unit (it takes 760 of them to equal one atmosphere), it is ideal for quantifying pressures far below normal air pressure.
You will find the torr used in many advanced scientific and industrial fields, including: