Torr (torr)
A unit of pressure approximately equal to 1 mmHg, used in vacuum engineering
The Torr (torr) is a unit of pressure with a history connected to the study of fluids, gases, and atmospheric phenomena. Evangelista Torricelli's invention of the barometer in 1643 was a landmark in pressure measurement, and subsequent work by Blaise Pascal established the mathematical foundations. The pascal — the SI unit — was named in Pascal's honor when the SI system was formalized. The Torr reflects either the SI tradition or the practical conventions of specific industries that standardized their measurements independently.
Accurate pressure measurement is critical in engineering, science, commerce, and everyday life. Using the correct unit and applying conversions precisely prevents errors that can be costly or dangerous in professional applications.
Conversion Table
| Unit | Symbol | 1 torr = |
|---|---|---|
| Pascal | Pa | 133.322 Pa |
| Kilopascal | kPa | 0.133322 kPa |
| Bar | bar | 0.00133322 bar |
| Atmosphere | atm | 0.00131579 atm |
| Pound per Square Inch | psi | 0.0193367 psi |
| Millimeters of Mercury | mmHg | 1 mmHg |
| Megapascal | MPa | 0.000133322 MPa |
| Gigapascal | GPa | 1.333220e-7 GPa |
| Kilopound per Square Inch | ksi | 0.0000193367 ksi |
| Inch of Mercury | inHg | 0.0393699 inHg |
| Kilogram-force per Square Centimeter | kgf/cm² | 0.00135951 kgf/cm² |
Conversions Involving Torr
Pascal → Torr
Pa → torr
Kilopascal → Torr
kPa → torr
Bar → Torr
bar → torr
Atmosphere → Torr
atm → torr
Pound per Square Inch → Torr
psi → torr
Millimeters of Mercury → Torr
mmHg → torr
Megapascal → Torr
MPa → torr
Gigapascal → Torr
GPa → torr
Kilopound per Square Inch → Torr
ksi → torr
Torr → Pascal
torr → Pa
Torr → Kilopascal
torr → kPa
Torr → Bar
torr → bar
Torr → Atmosphere
torr → atm
Torr → Pound per Square Inch
torr → psi
Torr → Millimeters of Mercury
torr → mmHg
Torr → Megapascal
torr → MPa
Torr → Gigapascal
torr → GPa
Torr → Kilopound per Square Inch
torr → ksi
Torr → Inch of Mercury
torr → inHg
Torr → Kilogram-force per Square Centimeter
torr → kgf/cm²
Inch of Mercury → Torr
inHg → torr
Kilogram-force per Square Centimeter → Torr
kgf/cm² → torr
Common Uses of the Torr
- •Automotive — inflating tires to manufacturer-specified pressures
- •Weather reporting — tracking barometric pressure for forecasting
- •Hydraulic systems — designing and operating fluid power equipment
- •Scuba diving — calculating safe dive depths based on partial pressures
- •Medical — measuring blood pressure and calibrating medical equipment
Did You Know?
The deepest point in the ocean — the Challenger Deep in the Mariana Trench — has a water pressure of approximately 110 MPa, or about 1,086 times standard atmospheric pressure. The Torr is one of several units used to express pressures across this extraordinary range.