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.
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.
What is kilopascal?
A kilopascal is a metric pressure unit equal to 1,000 pascals. It is used for weather forecasts, tire pressure specifications in metric countries, and structural and mechanical engineering calculations.
Real-world uses
Kilopascals are used for tyre pressure in most countries (standard car tyres are about 200–250 kPa), blood pressure in some medical systems, and hydraulic system specifications. Atmospheric pressure at sea level is approximately 101.325 kPa.
History
The kilopascal became a practical engineering unit with the adoption of the SI system. It offers a convenient scale for everyday pressure measurements, bridging the gap between the tiny pascal and the larger bar or atmosphere.
Common mistakes
Confusing kPa with psi when checking tyre pressure. 1 psi ≈ 6.895 kPa, so 32 psi ≈ 220 kPa. Inflating a tyre to 32 kPa instead of 220 kPa would leave it nearly flat.
When is this conversion used?
Converting between torr and kilopascal 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. Tyre pressure gauges, HVAC systems, and industrial equipment may use different pressure units depending on the manufacturer and region. Converting between psi, bar, and kPa is common in automotive and engineering work.
Worked examples
1 torr = 0.13332237 kilopascal
1 kilopascal = 1,000 pascal
How to convert torr to kilopascal
To convert torr to kilopascal, multiply the value by 0.13332237.
To convert kilopascal back to torr, multiply by 7.50061683.
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.
Quick reference: torr to kilopascal
| torr | kilopascal |
|---|---|
| 0.1 | 0.01333224 |
| 0.5 | 0.06666118 |
| 1 | 0.13332237 |
| 2 | 0.26664474 |
| 5 | 0.66661184 |
| 10 | 1.33322368 |
| 25 | 3.33305921 |
| 50 | 6.66611842 |
| 100 | 13.33223684 |
| 250 | 33.33059211 |
| 500 | 66.66118421 |
| 1,000 | 133.32236842 |
Common values
| torr | kilopascal | |
|---|---|---|
| Car tyre | 1,650.13570195 torr | 220 kilopascal |
| Standard atmosphere | 760 torr | 101.325 kilopascal |
| Blood pressure (systolic) | 120.00986923 torr | 16 kilopascal |
| Deep-sea submersible | 825,067.85097429 torr | 110,000 kilopascal |
| Bicycle tyre | 4,650.38243276 torr | 620 kilopascal |