Convert Torr to Atmospheres
1 torr is 0.001316 atm. One torr is exactly 0.00131578947368 atmospheres.
One torr is 0.0013157895 atmospheres. To convert torr to atmospheres, multiply by 0.0013157895; to go the other way, divide by 0.0013157895 or multiply by 760. The factor is exact rather than rounded: it follows from NIST Special Publication 811. Exactly one seven-hundred-and-sixtieth of a standard atmosphere.
Factor checked against the defining standard · How we check
- Torr × 0.0013157895
value * 0.001315789473680.001 atm
1 torr in every pressure unit
| Unit | Value | Exact factor |
|---|---|---|
| pounds per square inch | 0.0193367747 psi | × 0.0193367747046 |
| bars | 0.001333223684 bar | × 0.00133322368421 |
| pascals | 133.3223684 Pa | × 133.322368421 |
| kilopascals | 0.1333223684 kPa | × 0.133322368421 |
| megapascals | 0.0001333223684 MPa | × 0.000133322368421 |
| atmospheres | 0.001315789474 atm | × 0.00131578947368 |
| torr (as entered) | 1 Torr | — |
| inches of mercury | 0.03937006895 inHg | × 0.0393700689499 |
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 torr to atmospheres?
- 1.Take the measurement in torr.
- 2.Multiply by 0.0013157895 — that is how many atmospheres fit in one torr.
- 3.To go back the other way, divide by 0.0013157895, or multiply by 760.
Worked example: 25 torr to atmospheres
- Formula
- Torr × 0.0013157895 = atm
- Arithmetic
- 25 × 0.0013157895 = 0.032895 atm
- Answer
- 25 Torr = 0.032895 atm
The factor is rounded for display; the figure above is computed from the full value.
Torr to atmospheres conversion table
| Torr | Atmospheres |
|---|---|
| 1 Torr | 0.001316 atm |
| 2 Torr | 0.002632 atm |
| 3 Torr | 0.003947 atm |
| 4 Torr | 0.005263 atm |
| 5 Torr | 0.006579 atm |
| 6 Torr | 0.007895 atm |
| 7 Torr | 0.009211 atm |
| 8 Torr | 0.010526 atm |
| 9 Torr | 0.011842 atm |
| 10 Torr | 0.013158 atm |
| 12 Torr | 0.015789 atm |
| 15 Torr | 0.019737 atm |
| 20 Torr | 0.026316 atm |
| 25 Torr | 0.032895 atm |
| 50 Torr | 0.065789 atm |
| 100 Torr | 0.131579 atm |
| 200 Torr | 0.263158 atm |
| 300 Torr | 0.394737 atm |
| 500 Torr | 0.657895 atm |
| 1000 Torr | 1.315789 atm |
| 2000 Torr | 2.631579 atm |
| 5000 Torr | 6.578947 atm |
| 10000 Torr | 13.157895 atm |
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.
What is a standard atmosphere?
Exactly 101,325 pascals by definition, not by measurement — it was fixed as a reference, and the real pressure outside your window is never precisely it.
How many atmospheres are in a torr?
One torr is 0.0013157895 atmospheres. Going the other way, one standard atmosphere is 760 torr. 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 atmospheres are in a torr?
- 0.0013157895. Exactly 101,325 pascals by definition, not by measurement — it was fixed as a reference, and the real pressure outside your window is never precisely it.
- How do I convert atmospheres back to torr?
- Divide by 0.0013157895, or multiply by 760 — they are the same operation.
Other pressure conversions
Atmospheres to torr — the same conversion the other way.