Torr to Atmosphere Converter
Convert from Torr (mmHg) to Atmosphere (atm)
Understanding Torr and Atmosphere
The torr is a unit of pressure named after Evangelista Torricelli, who invented the mercury barometer.
- 1 torr is defined as 1/760 of standard atmospheric pressure
- Approximately equal to 1 mmHg (millimeter of mercury)
- Standard atmospheric pressure is 760 torr
- Commonly used in vacuum technology and some scientific applications
The atmosphere (atm) is a unit of pressure approximately equal to Earth's atmospheric pressure at sea level.
- 1 atm = 101,325 pascals (Pa)
- 1 atm = 760 torr (mmHg)
- 1 atm = 14.6959 PSI
- Used in chemistry, physics, and other scientific fields, particularly for expressing gas pressures
Conversion Formula
Torr to Atmosphere:
atm = torr ÷ 760
To convert from torr to atmospheres, divide the torr value by 760.
Atmosphere to Torr:
torr = atm × 760
To convert from atmospheres to torr, multiply the atmosphere value by 760.
Torr to Atmosphere Conversion Table
| Torr (mmHg) | Atmosphere (atm) |
|---|---|
| 76 | 0.1000 |
| 152 | 0.2000 |
| 228 | 0.3000 |
| 304 | 0.4000 |
| 380 | 0.5000 |
| 456 | 0.6000 |
| 532 | 0.7000 |
| 608 | 0.8000 |
| 684 | 0.9000 |
| 760 | 1.0000 |
Historical Context and Applications
Historical Development
Both the torr and atmosphere units have deep historical significance in the development of pressure measurement. The torr is named after Evangelista Torricelli, an Italian physicist who invented the mercury barometer in 1643. His experiments were one of the first to demonstrate the existence of atmospheric pressure and create a vacuum. The standard atmosphere was established as a unit much later, defined officially in the early 20th century as a standardized approximation of the mean sea-level atmospheric pressure on Earth.
Common Applications
- Torr: Most commonly used in vacuum science and technology. Laboratory vacuum systems, vacuum distillation, and semiconductor manufacturing all frequently use torr as the pressure unit. Also historically used in meteorology for barometric pressure readings.
- Atmosphere: Widely used in chemistry for gas laws and reactions, thermodynamics, and many theoretical calculations. It provides a convenient reference point, as 1 atm represents standard conditions. Often used in diving to express water pressure at depth.
Practical Examples
- Standard atmospheric pressure: 760 torr (1 atm)
- Rough laboratory vacuum: 1 torr (0.00132 atm)
- High vacuum: 10⁻⁶ torr (1.32×10⁻⁹ atm)
- Blood pressure (normal systolic): ~120 torr (0.158 atm)
- Pressure at 10m underwater: ~1520 torr (2 atm)
- Enter your value in the torr field
- The converter instantly displays the equivalent in atmospheres
- Use the swap button to convert from atmospheres to torr instead
- Results are displayed with 6 decimal places for precision
- For quick reference without calculations, refer to the conversion table above
This converter is particularly useful for scientists working with gas laws, vacuum systems, or for anyone needing to convert between these historically significant units of pressure measurement.