Torr to Atmospheres
Convert torr to atmospheres instantly — one torr is 0.00131579 atmospheres.
| Torr | Atmospheres |
|---|---|
| 1 Torr | 0.001316 atm |
| 2 Torr | 0.002632 atm |
| 3 Torr | 0.003947 atm |
| 5 Torr | 0.006579 atm |
| 10 Torr | 0.013158 atm |
| 25 Torr | 0.032895 atm |
| 50 Torr | 0.065789 atm |
| 100 Torr | 0.131579 atm |
How to use
- Enter a value in the Torr field.
- The Atmospheres figure appears immediately — no button to press.
- Typing in the Atmospheres field converts back to Torr the same way.
- Use the reference table for the values that come up most often.
Torr to Atmospheres formula
To convert torr to atmospheres, multiply by 0.00131578947.
atm = Torr × 0.00131578947
Put another way, one torr is exactly 1/760 of an atmosphere.
Why this factor: the torr and the atmosphere are both defined against the pascal, so dividing one definition by the other gives 0.00131578947 directly. Both definitions are set out in full below.
To go the other way, divide by 0.00131578947 — or use the Atmospheres to Torr converter, which is the same calculation reversed.
Worked example
Start with 32 Torr. Multiply by 0.00131578947 to get 0.042105 atm.
32 Torr × 0.00131578947 = 0.042105 atm
The converter above does this for any value you type, in either direction.
What is a torr?
A torr is a vacuum-measurement pressure unit, defined as one 760th of a standard atmosphere.
Definition: Exactly 101,325/760 pascals, which is about 133.3224 Pa. Named after Evangelista Torricelli.
Where it is used: Vacuum systems, mass spectrometry, and semiconductor process chambers.
Worth knowing: Almost identical to the mmHg but not exactly equal — they differ by about one part in seven million, which matters only in precision metrology.
What is an atmosphere?
A standard atmosphere is a fixed reference pressure, originally average sea-level air pressure.
Definition: Defined as exactly 101,325 pascals — an exact convention, not a measurement.
Where it is used: Chemistry reference conditions, diving pressure, and high-pressure physics.
Torr vs Atmospheres
The torr and the atmosphere belong to the same family of units, so converting between them is usually a matter of shifting a decimal point or applying a small whole-number factor.
Frequently asked questions
How many atmospheres are in a torr?
One torr equals 0.00131578947 atmospheres.
What is the formula to convert torr to atmospheres?
Multiply the number of torr by 0.00131578947. To reverse it, divide by 0.00131578947 instead.
How do I convert atmospheres back to torr?
Divide by 0.00131578947, which is the same as multiplying by 760.
How many atmospheres are in 10 torr?
10 Torr works out to 0.013158 atm.
Is there anything to watch out for with torr?
Almost identical to the mmHg but not exactly equal — they differ by about one part in seven million, which matters only in precision metrology.
How is the torr defined?
Exactly 101,325/760 pascals, which is about 133.3224 Pa. Named after Evangelista Torricelli.