Torr (Torr) to Inches of mercury (inHg) Conversion
Torr
The torr is a unit of pressure named after Evangelista Torricelli, the Italian physicist who invented the mercury barometer in 1643. One torr is defined as exactly 1/760 of a standard atmosphere (approximately 133.322 Pa). Numerically nearly identical to the millimetre of mercury (mmHg), it differs by less than 0.000015%. The torr is used in vacuum science and engineering: rough vacuum is 1–100 torr, fine vacuum 10⁻³–1 torr, and ultra-high vacuum below 10⁻⁹ torr.
Inches of mercury
The inch of mercury (inHg) is a unit of pressure equal to the pressure exerted by a column of mercury 1 inch (25.4 mm) high — approximately 3,386.39 Pa or 0.0334 atm. It is used in US aviation for altimeter settings (standard pressure is 29.92 inHg) and in US weather reports for barometric pressure. Pilots set their altimeters in inHg based on local barometric pressure to ensure accurate altitude readings.
| Torr (Torr) | Inches of mercury (inHg) |
|---|---|
| 0.1 Torr | 0.00394 inHg |
| 1 Torr | 0.0394 inHg |
| 2 Torr | 0.0787 inHg |
| 3 Torr | 0.1181 inHg |
| 5 Torr | 0.1969 inHg |
| 10 Torr | 0.3937 inHg |
| 20 Torr | 0.7874 inHg |
| 30 Torr | 1.1811 inHg |
| 50 Torr | 1.9685 inHg |
| 100 Torr | 3.937 inHg |
| 1000 Torr | 39.3701 inHg |
Frequently Asked Questions (FAQ)
How many inches of mercury are in 1 torr?
1 torr (Torr) is exactly 0.03937 inches of mercury (inHg).
How do I convert torr to inches of mercury?
Multiply the value in torr by 0.03937 to get the result in inches of mercury. Or use the converter above — type any number and see the result instantly.