Convert Inches of mercury to Torr
1 inch of mercury is 25.400006 Torr. One inch of mercury is exactly 25.4000063163 torr.
One inch of mercury is 25.400006 torr. To convert inches of mercury to torr, multiply by 25.400006; to go the other way, divide by 25.400006 or multiply by 0.039370069. The factor is exact rather than rounded: it follows from NIST Special Publication 811. The pressure of a one-inch column of mercury at 0 °C, fixed by convention at 3,386.389 pascals.
Factor checked against the defining standard · How we check
- Inches of mercury × 25.400006
value * 25.400006316325.4 Torr
1 inch of mercury in every pressure unit
| Unit | Value | Exact factor |
|---|---|---|
| pounds per square inch | 0.4911541996 psi | × 0.491154199634 |
| bars | 0.03386389 bar | × 0.03386389 |
| pascals | 3,386.389 Pa | × 3,386.389 |
| kilopascals | 3.386389 kPa | × 3.386389 |
| megapascals | 0.003386389 MPa | × 0.003386389 |
| atmospheres | 0.03342106094 atm | × 0.0334210609425 |
| torr | 25.40000632 Torr | × 25.4000063163 |
| inches of mercury (as entered) | 1 inHg | — |
Factors are entered by hand from NIST Special Publication 811 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert inches of mercury to torr?
- 1.Take the measurement in inches of mercury.
- 2.Multiply by 25.400006 — that is how many torr fit in one inch of mercury.
- 3.To go back the other way, divide by 25.400006, or multiply by 0.039370069.
Worked example: 25 inches of mercury to torr
- Formula
- inHg × 25.400006 = Torr
- Arithmetic
- 25 × 25.400006 = 635.000158 Torr
- Answer
- 25 inHg = 635.000158 Torr
The factor is rounded for display; the figure above is computed from the full value.
Inches of mercury to torr conversion table
| Inches of mercury | Torr |
|---|---|
| 1 inHg | 25.400006 Torr |
| 2 inHg | 50.800013 Torr |
| 3 inHg | 76.200019 Torr |
| 4 inHg | 101.600025 Torr |
| 5 inHg | 127.000032 Torr |
| 6 inHg | 152.400038 Torr |
| 7 inHg | 177.800044 Torr |
| 8 inHg | 203.200051 Torr |
| 9 inHg | 228.600057 Torr |
| 10 inHg | 254.000063 Torr |
| 12 inHg | 304.800076 Torr |
| 15 inHg | 381.000095 Torr |
| 20 inHg | 508.000126 Torr |
| 25 inHg | 635.000158 Torr |
| 50 inHg | 1,270.000316 Torr |
| 100 inHg | 2,540.000632 Torr |
| 200 inHg | 5,080.001263 Torr |
| 300 inHg | 7,620.001895 Torr |
| 500 inHg | 12,700.003158 Torr |
| 1000 inHg | 25,400.006316 Torr |
| 2000 inHg | 50,800.012633 Torr |
| 5000 inHg | 127,000.031582 Torr |
| 10000 inHg | 254,000.063163 Torr |
What is an inch of mercury?
The pressure of a one-inch column of mercury at 0 °C, fixed by convention at 3,386.389 pascals. US aviation altimeters and barometers read in it.
What is a torr?
Exactly one seven-hundred-and-sixtieth of a standard atmosphere. Within a millionth of a millimetre of mercury, which is what it replaced, and still the unit of vacuum work.
How many torr are in an inch of mercury?
One inch of mercury is 25.400006 torr. Going the other way, one torr is 0.039370069 inches of mercury. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every pressure unit here
| Unit | Symbol | One of these is |
|---|---|---|
| Pounds per square inch | psi | 6894.7573 pascal |
| Bars | bar | 100000 pascal |
| Pascals | Pa | the base unit |
| Kilopascals | kPa | 1000 pascal |
| Megapascals | MPa | 1000000 pascal |
| Atmospheres | atm | 101325 pascal |
| Torr | Torr | 133.32237 pascal |
| Inches of mercury | inHg | 3386.389 pascal |
Questions people actually ask
- How many torr are in an inch of mercury?
- 25.400006. Exactly one seven-hundred-and-sixtieth of a standard atmosphere. Within a millionth of a millimetre of mercury, which is what it replaced, and still the unit of vacuum work.
- How do I convert torr back to inches of mercury?
- Divide by 25.400006, or multiply by 0.039370069 — they are the same operation.
Other pressure conversions
Torr to inches of mercury — the same conversion the other way.