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Single conversion
To convert from hectopascal (hPa) to torr (torr), use the following formula:
Let's convert 5 hectopascal (hPa) to torr (torr).
Using the formula:
Therefore, 5 hectopascal (hPa) is equal to torr (torr).
Here are some quick reference conversions from hectopascal (hPa) to torr (torr):
| hectopascals | torr |
|---|---|
| 0.000001 hPa | torr |
| 0.001 hPa | torr |
| 0.1 hPa | torr |
| 1 hPa | torr |
| 2 hPa | torr |
| 3 hPa | torr |
| 4 hPa | torr |
| 5 hPa | torr |
| 6 hPa | torr |
| 7 hPa | torr |
| 8 hPa | torr |
| 9 hPa | torr |
| 10 hPa | torr |
| 20 hPa | torr |
| 30 hPa | torr |
| 40 hPa | torr |
| 50 hPa | torr |
| 100 hPa | torr |
| 1000 hPa | torr |
| 10000 hPa | torr |
For all Pressure converters, choose units using the From/To dropdowns above.
A hectopascal (hPa) is a metric unit used to measure pressure.
You will most commonly see it in weather reports to describe atmospheric pressure (also known as barometric pressure).
If you've seen millibars (mbar) on older weather maps, the hectopascal is its modern replacement.
The switch was simple for meteorologists because the units are exactly the same (1 hPa = 1 mbar).
The hectopascal is now the international standard for measuring atmospheric pressure, making weather data consistent worldwide.
The conversion is in the name. The prefix "hecto-" means 100. This makes the math simple:
Just as "hecto-" means 100, "kilo-" means 1,000. This defines their relationship:
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: