Convert Standard atmosphere to Torr
1 standard atmosphere = 760 torr (Torr). For example, 10 standard atmosphere = 7,600 torr and 100 standard atmosphere = 76,000 torr. Type any value below to convert standard atmosphere to torr both ways — it runs entirely in your browser.
Quick answer: Standard atmosphere to Torr
1 Standard atmosphere = 760 Torr (atm → Torr). To convert standard atmosphere to torr, multiply by 760. To convert torr to standard atmosphere, multiply by 0.001315789. The converter at the top does this instantly and both ways; the sections below give the formula, worked examples, a full conversion chart and answers to the most common standard atmosphere-to-torr questions.
How to convert Standard atmosphere to Torr
To convert standard atmosphere to torr, multiply the number of standard atmosphere by the conversion factor 760, because 1 atm = 760 Torr. The conversion is linear, so the same factor works for any value — whole numbers, decimals or fractions. For the reverse direction, 1 Torr = 0.001315789 atm, so you divide by 760 (or multiply by 0.001315789) to turn torr back into standard atmosphere.
Torr = atm × 760 ·
atm = Torr × 0.001315789
- Write down the value you want to convert, in standard atmosphere.
- Multiply it by 760.
- The result is the same area/length/quantity expressed in torr.
Standard atmosphere to Torr — worked examples
Each row shows the exact arithmetic so you can follow the conversion step by step. For example, 5 standard atmosphere is 3,800 torr because 5 atm × 760 = 3,800 Torr.
| Standard atmosphere | Calculation | Torr |
|---|---|---|
| 1 atm | 1 atm × 760 = 760 Torr | 760 Torr |
| 2 atm | 2 atm × 760 = 1,520 Torr | 1,520 Torr |
| 3 atm | 3 atm × 760 = 2,280 Torr | 2,280 Torr |
| 5 atm | 5 atm × 760 = 3,800 Torr | 3,800 Torr |
| 7 atm | 7 atm × 760 = 5,320 Torr | 5,320 Torr |
| 10 atm | 10 atm × 760 = 7,600 Torr | 7,600 Torr |
| 12 atm | 12 atm × 760 = 9,120 Torr | 9,120 Torr |
| 15 atm | 15 atm × 760 = 11,400 Torr | 11,400 Torr |
| 20 atm | 20 atm × 760 = 15,200 Torr | 15,200 Torr |
| 25 atm | 25 atm × 760 = 19,000 Torr | 19,000 Torr |
| 50 atm | 50 atm × 760 = 38,000 Torr | 38,000 Torr |
| 100 atm | 100 atm × 760 = 76,000 Torr | 76,000 Torr |
Common Standard atmosphere to Torr conversions
These are the standard atmosphere-to-torr values people look up most often. Every figure is computed from the exact factor, so you can rely on them for quick reference:
- 1 standard atmosphere = 760 torr
- 2 standard atmosphere = 1,520 torr
- 2.5 standard atmosphere = 1,900 torr
- 3 standard atmosphere = 2,280 torr
- 4 standard atmosphere = 3,040 torr
- 5 standard atmosphere = 3,800 torr
- 6 standard atmosphere = 4,560 torr
- 7 standard atmosphere = 5,320 torr
- 8 standard atmosphere = 6,080 torr
- 9 standard atmosphere = 6,840 torr
- 10 standard atmosphere = 7,600 torr
- 12 standard atmosphere = 9,120 torr
- 15 standard atmosphere = 11,400 torr
- 20 standard atmosphere = 15,200 torr
- 25 standard atmosphere = 19,000 torr
- 30 standard atmosphere = 22,800 torr
- 50 standard atmosphere = 38,000 torr
- 75 standard atmosphere = 57,000 torr
- 100 standard atmosphere = 76,000 torr
- 200 standard atmosphere = 152,000 torr
- 500 standard atmosphere = 380,000 torr
- 1000 standard atmosphere = 760,000 torr
Standard atmosphere to Torr conversion chart (both directions)
The chart below converts standard atmosphere to torr and torr to standard atmosphere side by side, so it works whichever way you need. 1 standard atmosphere = 760 torr, and 1 torr = 0.001315789 standard atmosphere.
| Standard atmosphere → Torr | Torr → Standard atmosphere |
|---|---|
| 0.25 atm = 190 Torr | 0.25 Torr = 0.0003289474 atm |
| 0.5 atm = 380 Torr | 0.5 Torr = 0.0006578947 atm |
| 1 atm = 760 Torr | 1 Torr = 0.001315789 atm |
| 2 atm = 1,520 Torr | 2 Torr = 0.002631579 atm |
| 3 atm = 2,280 Torr | 3 Torr = 0.003947368 atm |
| 4 atm = 3,040 Torr | 4 Torr = 0.005263158 atm |
| 5 atm = 3,800 Torr | 5 Torr = 0.006578947 atm |
| 6 atm = 4,560 Torr | 6 Torr = 0.007894737 atm |
| 7 atm = 5,320 Torr | 7 Torr = 0.009210526 atm |
| 8 atm = 6,080 Torr | 8 Torr = 0.01052632 atm |
| 9 atm = 6,840 Torr | 9 Torr = 0.01184211 atm |
| 10 atm = 7,600 Torr | 10 Torr = 0.01315789 atm |
| 12 atm = 9,120 Torr | 12 Torr = 0.01578947 atm |
| 15 atm = 11,400 Torr | 15 Torr = 0.01973684 atm |
| 20 atm = 15,200 Torr | 20 Torr = 0.02631579 atm |
| 25 atm = 19,000 Torr | 25 Torr = 0.03289474 atm |
| 30 atm = 22,800 Torr | 30 Torr = 0.03947368 atm |
| 40 atm = 30,400 Torr | 40 Torr = 0.05263158 atm |
| 50 atm = 38,000 Torr | 50 Torr = 0.06578947 atm |
| 75 atm = 57,000 Torr | 75 Torr = 0.09868421 atm |
| 100 atm = 76,000 Torr | 100 Torr = 0.1315789 atm |
| 150 atm = 114,000 Torr | 150 Torr = 0.1973684 atm |
| 200 atm = 152,000 Torr | 200 Torr = 0.2631579 atm |
| 250 atm = 190,000 Torr | 250 Torr = 0.3289474 atm |
| 500 atm = 380,000 Torr | 500 Torr = 0.6578947 atm |
| 1000 atm = 760,000 Torr | 1000 Torr = 1.315789 atm |
Standard atmosphere vs Torr: which is bigger?
A standard atmosphere is the larger unit: one standard atmosphere equals 760 torrs. Put another way, you need 760 torrs to make a single standard atmosphere.
What is a Standard atmosphere? History, origin and usage
The standard atmosphere was fixed by the 10th General Conference on Weights and Measures in 1954 at exactly 101,325 pascals. Before that, "one atmosphere" meant whatever a 760 mm mercury column happened to weigh, which depended on local gravity and on the temperature of the mercury — so the same experiment gave slightly different answers in different laboratories. Fixing it as a defined number ended that.
Atmospheres are used in chemistry, physics, diving and any field that talks about pressure as a multiple of ordinary air pressure — reaction conditions, gas laws, hyperbaric medicine and pressure-vessel ratings.
It is a defined constant, not a measurement, so it never changes with the weather or with where you are standing. Real sea-level pressure wanders a few per cent either side of it every week. The deepest point of the ocean sits at roughly 1,100 atmospheres.
What is a Torr? History, origin and usage
The torr honours Evangelista Torricelli, who built the first mercury barometer in 1643 and correctly explained that the column was held up by the weight of the air outside. The unit was named in the 1940s, and was defined as exactly one 760th of a standard atmosphere so that it would be tied to a fixed number rather than to the behaviour of real mercury.
Torr is the working unit of vacuum technology — vacuum pumps, freeze dryers, electron microscopes, semiconductor process chambers and mass spectrometers are all specified in torr or its subdivisions.
Because it is defined as a 760th of an atmosphere, 760 torr is one atmosphere exactly, by construction. It is very nearly the same as a millimetre of mercury but not exactly: the two differ by about one part in seven million, a gap that matters only in precision metrology and is the reason careful documents never treat the two names as interchangeable.
Convert 1 Standard atmosphere to other units
It can help to see a standard atmosphere next to the other units it is commonly compared with. One standard atmosphere (atm) is equal to:
| 1 Standard atmosphere equals | Unit |
|---|---|
| 101,325 Pa | Pascal |
| 1,013.25 hPa | Hectopascal |
| 101.325 kPa | Kilopascal |
| 0.101325 MPa | Megapascal |
| 1,013.25 mbar | Millibar |
| 1.01325 bar | Bar |
| 760 Torr | Torr |
| 759.9999 mmHg | Millimetre of mercury |
| 29.92126 inHg | Inch of mercury |
| 10,332.27 mmH₂O | Millimetre of water |
| 406.7825 inH₂O | Inch of water |
| 14.69595 psi | Pound per square inch |
| 1.033227 kgf/cm² | Kilogram-force per square centimetre |
Convert 1 Torr to other units
One torr (Torr) is equal to:
| 1 Torr equals | Unit |
|---|---|
| 133.3224 Pa | Pascal |
| 1.333224 hPa | Hectopascal |
| 0.1333224 kPa | Kilopascal |
| 0.0001333224 MPa | Megapascal |
| 1.333224 mbar | Millibar |
| 0.001333224 bar | Bar |
| 0.001315789 atm | Standard atmosphere |
| 0.9999999 mmHg | Millimetre of mercury |
| 0.03937007 inHg | Inch of mercury |
| 13.5951 mmH₂O | Millimetre of water |
| 0.5352401 inH₂O | Inch of water |
| 0.01933677 psi | Pound per square inch |
| 0.00135951 kgf/cm² | Kilogram-force per square centimetre |
Tips for converting Standard atmosphere to Torr
- To go from standard atmosphere to torr, multiply by 760; to go back, divide by 760 (or multiply by 0.001315789).
- For a quick mental estimate, remember that 1 standard atmosphere ≈ 760 torr, so 10 standard atmosphere ≈ 7,600 torr.
- The converter above keeps full precision; the tables round for readability, so use the tool for exact figures.
- Both fields update live as you type — change either side to convert in that direction.
How to use this Standard atmosphere to Torr converter
Type a number into the Standard atmosphere field and the equivalent in Torr appears instantly — there is no “convert” button to press and nothing is sent to a server, so it works offline once the page has loaded and is safe for any data. You can also type into the Torr field to convert the other way (torr to standard atmosphere). Use the swap control to flip the two units, and copy the result with a single click. Because the calculation runs in your browser with full floating-point precision, the converter is more exact than the rounded figures shown in the reference chart above — use the chart for quick look-ups and the tool for precise work.
Accuracy and method
Every figure on this page — the formula, the worked examples, the conversion chart and the “convert to other units” tables — is computed from a single verified conversion factor (1 atm = 760 Torr), never copied from a hand-typed lookup table that could drift. That factor is derived from each unit’s definition in terms of a common base unit, and an automated check re-verifies all of the site’s factors on every update, so the numbers here stay correct over time. This matters for standard atmosphere-to-torr conversions because a small rounding error in a published table compounds quickly at larger quantities; computing from the exact factor avoids that.
Sources
- BIPM — The International System of Units (SI Brochure) — the defining document for the SI, published by the International Bureau of Weights and Measures. It fixes the base unit that this conversion resolves to, which is why the factor here can be exact rather than approximate.
- NIST — Definitions of the SI base units — the US National Institute of Standards and Technology reference for the SI base units, used here as an independent cross-check on the base-unit definition.
Pressure factors here come from fixed definitions, anchored to the pascal: a bar is exactly 100,000 Pa, one atmosphere is exactly 101,325 Pa, a torr is exactly a 760th of an atmosphere, and psi is built from the exact pound and the exact inch. Two of them — psi and the torr — work out to decimals that repeat forever, so where a number is shown rounded it is marked, not quietly trimmed.
Frequently asked questions
- How many torr are in 1 standard atmosphere?
- 1 standard atmosphere = 760 torr (Torr). To convert any number of standard atmosphere to torr, multiply by 760.
- How do I convert standard atmosphere to torr?
- Multiply the number of standard atmosphere by 760. For example, 10 standard atmosphere = 10 × 760 = 7,600 torr, and 25 standard atmosphere = 19,000 torr.
- How many standard atmosphere are in 1 torr?
- 1 torr = 0.001315789 standard atmosphere. So to convert torr back to standard atmosphere, multiply by 0.001315789.
- What is the formula to convert standard atmosphere to torr?
- torr = standard atmosphere × 760. The reverse formula is standard atmosphere = torr × 0.001315789.
- How much is 100 standard atmosphere in torr?
- 100 standard atmosphere = 76,000 torr. (And 1000 standard atmosphere = 760,000 torr.)
- Which is bigger, a standard atmosphere or a torr?
- A standard atmosphere is larger: 1 standard atmosphere = 760 torr.
- Is this standard atmosphere to torr converter accurate?
- Yes — every value is computed from the exact 760 Torr per atm factor (not rounded look-up tables), and the factors are re-verified automatically on every update.
- Can I convert torr to standard atmosphere too?
- Yes. The converter works both ways — enter a value in either field. 1 torr = 0.001315789 standard atmosphere.