Convert pressure units — Pascal, bar, PSI, atm, Torr, mmHg.
| Unit | Name | Value |
|---|---|---|
| Pa | Pascal | 101325 |
| kPa | Kilopascal | 101.325 |
| bar | Bar | 1.01325 |
| psi | PSI | 14.695943 |
| Torr | Torr / mmHg | 760.0021 |
| inHg | Inch of Mercury | 29.921244 |
Formula: Torr = Atmosphere × 760
Multiply any atmosphere value by 760 to get torr.
Reverse: Atmosphere = Torr × 0.001316
Common atmosphere values — factor: 1 atm = 760 Torr
| Atmosphere (atm) | Torr (Torr) | Context |
|---|---|---|
| 0.001 atm | 0.76 Torr | Vacuum |
| 0.01 atm | 7.6 Torr | High vacuum |
| 0.1 atm | 76 Torr | Mountain top |
| 0.5 atm | 380 Torr | Half atmosphere |
| 1 atm | 760 Torr | Sea level |
| 2 atm | 1,520 Torr | 10 m water depth |
| 5 atm | 3,800 Torr | 40 m depth |
| 10 atm | 7,600 Torr | 90 m depth |
| 50 atm | 3.8e+04 Torr | 500 m depth |
| 100 atm | 7.6e+04 Torr | 1 km depth |
| 500 atm | 380,000 Torr | 5 km depth |
| 1,000 atm | 760,000 Torr | 10 km depth |
| 5,000 atm | 3,800,000 Torr | Deep mantle |
| 1e+04 atm | 7,600,000 Torr | Very deep mantle |
| 5e+04 atm | 38,000,000 Torr | Diamond formation |
1 atm = 760 Torr. Memorize for instant estimates.
Use 760 as a quick mental multiplier.
Multiply result by 0.001316 to recover the original atm value.
Uses atmospheres in gas law calculations (PV = nRT) and solubility studies.
Calculates dive depth pressure (every 10 m adds ~1 atm) for dive tables.
Designs diamond anvil cell experiments measuring pressure in thousands of atm.
Specifies autoclave and reactor operating pressures relative to atm.
Estimates metamorphic rock formation pressures in kbar (thousands of atm).
Plans saturation diving operations using atm for depth-pressure calculations.
The atmosphere (atm) is defined as exactly 101,325 pascals — the approximate air pressure at sea level. It was originally defined as the average atmospheric pressure at sea level at 45° latitude, and has been a standard reference since the 17th century.
Atmospheres are used in chemistry (gas laws), scuba diving depth calculations (every 10 m of water ≈ 1 additional atm), and as a convenient reference for extreme pressure comparisons.
Interesting fact: Jupiter's atmosphere has pressures exceeding 1,000 atm at depth. Diamond formation in Earth's mantle requires pressures of 45,000–60,000 atm at depths of 150–200 km.
The torr was named after Evangelista Torricelli, who invented the mercury barometer in 1644. One torr is defined as 1/760 of standard atmospheric pressure (133.322 Pa), and is equal to 1 mmHg at 0°C.
Torr is the standard pressure unit in vacuum science and semiconductor manufacturing. High vacuum systems operate at 10⁻³ to 10⁻⁷ torr. Ultra-high vacuum (used in particle accelerators) reaches below 10⁻¹⁰ torr.
Interesting fact: Torricelli's original barometer experiment used a 1-meter tube of mercury that settled at 760 mm above the reservoir — directly defining the unit that would later bear his name.
Converting atmosphere to torr is a common task in engineering, medicine, meteorology, and science. Different industries and countries use different pressure units — PSI in the US, bar in Europe, mmHg in medicine, and pascals in physics — making accurate conversion essential for cross-disciplinary work.
Quick reference: 5 atm = 3800 Torr and 10 atm = 7600 Torr. For the reverse: 1 Torr = 0.001316 atm. The exact factor is 1 atm = 760 Torr.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.