torr (Torr)
1 torr = 133.32236842 pascals
What is torr?
A torr is a pressure unit equal to approximately 1/760 of an atmosphere. It is used in vacuum technology, low-pressure experimental physics, and blood pressure measurement in older clinical literature.
Notes: Vacuum unit
Real-world uses
Torr is used in vacuum technology, semiconductor manufacturing, and blood pressure measurement (mmHg ≈ torr). Vacuum chambers for electron beam welding operate at about 10⁻⁵ torr, and freeze-drying processes typically operate at 0.1–1 torr.
History
Named after Evangelista Torricelli, who invented the mercury barometer in 1644. The torr was defined to approximate the pressure exerted by 1 mm of mercury. It was formally standardized as 1/760 of a standard atmosphere.
Common mistakes
Assuming torr and mmHg are exactly the same—they are nearly identical but differ by about 0.000015%. For most purposes they are interchangeable, but ultra-precise vacuum work may require distinction.
When is this conversion used?
Converting between torr and pascal is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region.
How to convert torr to pascal
To convert torr to pascal, multiply the value by 133.32236842.
Conversion formula (from base unit)
x * 133.3223684211
Measurement standards
The pascal (Pa) is the SI derived unit of pressure, defined as one newton per square metre. The World Meteorological Organization mandates the hectopascal (hPa) for atmospheric pressure reporting in aviation and weather services.
Did you know?
The pressure at the bottom of the Mariana Trench, nearly 11 km deep, exceeds 1,086 bar — over a thousand times atmospheric pressure. At this depth, water is compressed by about 5%, making it measurably denser than at the surface.
| torr | pascals |
|---|---|
| 0.1 | 13.33223684 |
| 0.5 | 66.66118421 |
| 1 | 133.32236842 |
| 2 | 266.64473684 |
| 5 | 666.61184211 |
| 10 | 1,333.22368421 |
| 25 | 3,333.05921053 |
| 50 | 6,666.11842105 |
| 100 | 13,332.23684211 |
| 250 | 33,330.59210528 |
| 500 | 66,661.18421055 |
| 1,000 | 133,322.3684211 |
Common values
| torr | pascals | |
|---|---|---|
| Car tyre | 1,650.13570195 torr | 220,000 pascals |
| Standard atmosphere | 760 torr | 101,325 pascals |
| Blood pressure (systolic) | 120.00986923 torr | 16,000 pascals |
| Deep-sea submersible | 825,067.85097429 torr | 110,000,000 pascals |
| Bicycle tyre | 4,650.38243276 torr | 620,000 pascals |
Full torr conversion table
| Unit | Value | Factor |
|---|---|---|
| pascal | 1 Torr = 133.32236842 Pa | × 133.32236842 |
| kilopascal | 1 Torr = 0.13332237 kPa | × 0.13332237 |
| bar | 1 Torr = 0.00133322 bar | × 0.00133322 |
| pound per square inch | 1 Torr = 0.01933677 psi | × 0.01933677 |
| atmosphere | 1 Torr = 0.00131579 atm | × 0.00131579 |
| millibar | 1 Torr = 1.33322368 mbar | × 1.33322368 |
| hectopascal | 1 Torr = 1.33322368 hPa | × 1.33322368 |
| inch of mercury | 1 Torr = 0.03937007 inHg | × 0.03937007 |
| megapascal | 1 Torr = 0.00013332 MPa | × 0.00013332 |