Our atm-to-psi converter provides instant and reliable pressure unit conversions for scientists, engineers, and students. Converting atmospheres to pounds per square inch is a common requirement in physics, chemistry, diving, and aerospace applications. Enter your atm value and receive the psi equivalent immediately in the browser.
This page uses the shared pressure calculator that currently supports only six units: pascals, kilopascals, bar, atmospheres, psi, and millimeters of mercury. The default pair here is atm to psi. The interface does not add a gauge-versus-absolute switch, altitude compensation, fluid-depth modeling, or weather simulation, so the examples below stay inside the six units and constants exposed by the component.
The shared pressure component defines 1 atmosphere as 101,325 pascals and 1 psi as 6,894.76 pascals. Using those built-in constants, 1 atm converts to 14.695943005993 psi on this route.
To convert a pressure value from atm to psi, use the following equation:
PSI = ATM x 14.695943005993
This conversion factor comes from dividing the component constants of 101,325 pascals per atmosphere and 6,894.76 pascals per psi. For hand calculations, rounding to 14.696 is usually sufficient, but the page itself follows the longer factor above.
The key equivalences are:
1 ATM = 14.695943005993 PSI
1 PSI = 0.068046 ATM
These values describe the shared pressure calculator as implemented on this route.
Follow these steps to convert any atm value to psi manually:
Step 1: Identify your pressure value in atmospheres. For example, let us use 3 atm, a pressure commonly encountered in shallow diving and hyperbaric medicine.
Step 2: Multiply the atm value by 14.696. So 3 x 14.696 = 44.088.
Step 3: Round to the appropriate precision. In this case, 3 atm equals approximately 44.09 psi.
Step 4: Verify your result. Since 1 atm is about 14.7 psi, 3 atm should be about 3 times 14.7, which is 44.1 psi. This confirms our calculation is correct.
Let us try another example with a fractional atmosphere value. Convert 0.5 atm to psi:
Step 1: Start with 0.5 atm.
Step 2: Multiply by 14.696: 0.5 x 14.696 = 7.348.
Step 3: Therefore, 0.5 atm equals approximately 7.35 psi. This represents roughly half of standard sea-level atmospheric pressure and corresponds to the ambient pressure at an altitude of approximately 5,500 meters or 18,000 feet above sea level.
The standard atmosphere, abbreviated as atm, is a unit of pressure defined as exactly 101,325 pascals. It was originally intended to represent the average atmospheric pressure at sea level under standard conditions. The atmosphere is widely used in chemistry, physics, and engineering as a convenient reference unit. Gas laws such as Boyle's law and the ideal gas law are frequently expressed using atmospheres as the pressure unit, making it a fundamental part of scientific education and research.
PSI, or pounds per square inch, measures pressure as the force in pounds exerted over one square inch of area. It is the dominant pressure unit in the United States for industrial, automotive, and consumer applications. While the scientific community generally prefers SI units like pascals or atmospheres, psi remains essential in practical American engineering, construction, and manufacturing contexts.
The need to convert atm to psi arises most often when translating scientific data into practical engineering specifications, or when working with equipment that displays pressure in psi while reference materials use atmospheres. For the broader six-unit selector, use our shared pressure converter tool. For nearby conversions in the same cluster, our kPa to psi converter and bar to psi converter cover two of the other common routes exposed by the shared component.
Scuba Diving and Underwater Pressure: Divers frequently work with pressure expressed in atmospheres. At sea level, the ambient pressure is 1 atm. For every 10 meters (approximately 33 feet) of seawater depth, pressure increases by roughly 1 atm. A diver at 30 meters depth experiences approximately 4 atm of absolute pressure, which equals about 58.78 psi. Understanding this conversion is critical for calculating safe ascent rates, managing decompression stops, and selecting appropriate breathing gas mixtures.
Chemistry and Gas Laws: In chemistry, gas pressures are routinely expressed in atmospheres. The ideal gas law, PV = nRT, commonly uses atmospheres for pressure when the gas constant R is given as 0.08206 L atm per mol per K. When laboratory equipment such as pressure regulators and gauges display readings in psi, chemists must convert to verify that experimental conditions match theoretical calculations. A reaction vessel at 5 atm operates at approximately 73.48 psi.
Hyperbaric Medicine: Hyperbaric oxygen therapy chambers operate at pressures above 1 atm, typically between 1.5 and 3 atm. Medical professionals prescribe treatment pressures in atmospheres, but the chamber gauges and safety systems may display psi. A treatment pressure of 2.4 atm equals approximately 35.27 psi. Accurate conversion is essential for patient safety and treatment efficacy in these clinical settings.
Aerospace and Aviation: Aircraft cabin pressurization is often discussed in terms of atmospheres or equivalent altitude. Commercial aircraft cabins are typically pressurized to about 0.75 atm, equivalent to approximately 11.02 psi, which simulates an altitude of roughly 2,400 meters or 8,000 feet. Engineers designing pressurization systems must convert between atm and psi when working with American-manufactured components and international safety standards.
Autoclave and Sterilization: Medical and laboratory autoclaves operate at elevated pressures to achieve sterilization temperatures. A typical autoclave runs at about 2 atm absolute pressure, which equals approximately 29.39 psi. The pressure specifications for these devices may be listed in either unit depending on the manufacturer, so healthcare facility managers and laboratory technicians must be comfortable converting between them. For related conversions involving other pressure units, you can also use our kPa to psi converter for kilopascal-based specifications.
Here are some helpful shortcuts for converting atm to psi quickly:
The Multiply-by-15 Shortcut: For a fast mental estimate, multiply the atm value by 15. Since 1 atm equals about 14.696 psi on this route, multiplying by 15 gives a result that is only about 2 percent higher than the tool value. For example, 2 atm times 15 equals 30 psi. The calculator returns about 29.39 psi.
The Diving Rule of Thumb: Every atmosphere of pressure equals roughly 14.7 psi. Divers can use this to quickly estimate absolute pressure at depth. At 10 meters underwater, total pressure is about 2 atm or 29.4 psi. At 20 meters, it is about 3 atm or 44.1 psi. At 30 meters, it is about 4 atm or 58.8 psi. This linear progression makes depth-to-pressure calculations straightforward.
Memorize the Key Value: The single most important number to remember for this page is that 1 atm equals 14.695943005993 psi. From that one factor, you can derive any conversion by simple multiplication. Two atm is about 29.39 psi, five atm is about 73.48 psi, and ten atm is about 146.96 psi.
If you need to move between other units in the same pressure cluster, the shared pressure converter and the psi to bar converter are the closest companion tools.
| ATM | PSI |
|---|---|
| 0.25 | 3.67 |
| 0.5 | 7.35 |
| 0.75 | 11.02 |
| 1 | 14.70 |
| 1.5 | 22.04 |
| 2 | 29.39 |
| 2.5 | 36.74 |
| 3 | 44.09 |
| 4 | 58.78 |
| 5 | 73.48 |
| 6 | 88.18 |
| 7 | 102.87 |
| 8 | 117.57 |
| 10 | 146.96 |
| 15 | 220.44 |
| 20 | 293.92 |
| 50 | 734.80 |
| 100 | 1469.59 |
The conversion factor on this page is 14.695943005993. You multiply any pressure value in atmospheres by that number to obtain the psi value returned by the shared component. The factor comes from the component constants of 101,325 pascals per atmosphere and 6,894.76 pascals per psi. For quick mental math, rounding to 14.7 is still useful.
One atmosphere equals 14.695943005993 psi in this calculator. That value comes directly from the shared component constants and serves as the baseline for every atm-to-psi result shown on this route. For quick estimation, remembering 1 atm is roughly 14.7 psi is usually enough.
One atmosphere equals 1.01325 bar, so the two units are very close but not identical. The atmosphere is defined based on the average pressure of the Earth's atmosphere at sea level, while the bar is defined as exactly 100,000 pascals for mathematical convenience. The difference between them is about 1.3 percent. In many casual contexts, 1 atm and 1 bar are treated as approximately equal, but for precise scientific and engineering work, the distinction is important. Both units are commonly used in different fields and regions around the world.
Pressure cookers typically operate at 1 to 2 atm above atmospheric pressure, meaning the absolute pressure inside is 2 to 3 atm. To find the gauge pressure in psi, multiply only the excess pressure above atmospheric by 14.696. A pressure cooker operating at 1 atm gauge pressure (2 atm absolute) has an internal gauge pressure of about 14.7 psi. A high-pressure setting of 1.5 atm gauge (2.5 atm absolute) corresponds to approximately 22 psi gauge pressure. These values help when comparing pressure cooker specifications listed in different units.
The atmosphere became the standard pressure unit in chemistry largely for historical and practical reasons. Early chemists measured gas pressures using mercury barometers, and standard atmospheric pressure was defined as the pressure that supports a column of mercury 760 millimeters tall. This definition predates the SI system and became deeply embedded in chemical education, textbooks, and the formulation of gas laws. The ideal gas constant R is most commonly memorized as 0.08206 L atm per mol per K, reinforcing the use of atmospheres in chemical calculations. While the SI unit pascal is increasingly used in modern research, atmospheres remain prevalent in educational settings and many published reference materials.
At 20 meters depth in seawater, a diver experiences approximately 3 atm of absolute pressure, which equals about 44.09 psi. This total pressure consists of 1 atm from the atmosphere above the water surface plus approximately 2 atm from the weight of the water column. The pressure increases by roughly 1 atm for every 10 meters of seawater depth. At this pressure, the volume of gas in a diver's lungs and equipment is compressed to about one-third of its surface volume, according to Boyle's law. This compression effect is why divers must equalize their ears and sinuses during descent.
Atmospheric pressure decreases with increasing altitude because there is less air above to exert downward force. At sea level, atmospheric pressure is 1 atm or 14.696 psi. At 1,500 meters (about 5,000 feet), it drops to roughly 0.83 atm or 12.2 psi. At 3,000 meters (about 10,000 feet), it falls to approximately 0.69 atm or 10.1 psi. At the summit of Mount Everest at 8,849 meters, atmospheric pressure is only about 0.33 atm or 4.9 psi. This pressure reduction affects everything from cooking times to engine performance and human physiology.
Historically, people often pair 1 atmosphere with 760 mmHg. On this site, however, the shared pressure component uses 133.322 pascals for mmHg and 101,325 pascals for atm, so 760 mmHg converts to about 0.999997 atm rather than a perfectly exact 1 atm. That distinction matters when you want this page and the mmHg route to stay aligned to the same implementation.
Use this page when the source pressure is already in atmospheres and the next workflow wants psi. That is common in lab references, pressure-system notes, and educational comparisons where an atmosphere-based value needs to be translated into a more familiar psi reading.
If the session also needs bar or kPa, the shared pressure converter is more flexible. This route is strongest when the question is specifically about atmospheres-to-psi rather than a wider pressure-unit comparison.
Check whether the destination is using absolute or gauge pressure language, because the unit conversion alone does not resolve that distinction. For adjacent routes, use kPa to PSI Converter or Bar to PSI Converter depending on the next source unit you encounter.
That keeps the page honest and useful. It translates the unit directly and leaves measurement context where it belongs.
Convert atmospheres to PSI instantly.