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PSI to Atmospheres Converter
↔ Convert atm to psi instead

Common Conversions

psi atm
1 0.068
5 0.34
10 0.68
14.696 1
25 1.701
50 3.402
100 6.805
200 13.609
500 34.023
1000 68.046
2000 136.092
2200 149.701

Why this conversion matters in chemistry

psi is the unit you'll see on most gas regulators and gauges in US labs — a standard nitrogen cylinder reads around 2200 psi when full, a steam autoclave holds about 15 psi gauge to reach 121°C. Chemistry calculations almost always want atm (or kPa) instead, so the conversion is the bridge between what the regulator shows and what the ideal gas law wants. Dividing by 14.696 gives you 2200 psi = 150 atm, or 15 psi = 1 atm gauge (about 2 atm absolute — gauge pressures sit on top of atmospheric). Worth keeping the factor mental; it comes up every time someone hands you a pressure reading and expects a molar quantity back.

Formula

atm = psi / 14.696

Worked Examples

14.696 psi = 1 atm

The anchor conversion. Sea-level atmospheric pressure by definition, and where most psi-to-atm conversions pivot.

29.4 psi = 2 atm

Roughly the absolute pressure a steam autoclave hits during sterilization — enough to push water's boiling point above 120°C.

2200 psi = 149.7 atm

A full compressed gas cylinder — nitrogen, argon, helium. The number you read off the high-pressure gauge on a regulator.

100 psi = 6.805 atm

Moderate elevated pressure, common for benchtop catalytic hydrogenation runs.

Frequently Asked Questions

How do I convert psi to atm?
Divide by 14.696. So 100 psi is 6.805 atm, 2200 psi is roughly 150 atm. The factor comes from the definition: 1 atm is exactly 14.696 psi, which is the pressure that supports 760 mm of mercury at sea level.
Why do US gas cylinders read in psi?
Historical convention. Industrial gas standards in the US grew up around pressure gauges built for engineering applications, which all use psi. A full nitrogen cylinder reads about 2200 psi (~150 atm); most chemistry calculations want that number in atm or kPa, which is what the conversion is for.
What's the relationship between psi and atm?
1 atm is 14.696 psi exactly, and 1 psi is 0.06805 atm. The psi is defined as a pound-force per square inch — engineering origin — while atm was originally defined by mercury-barometer measurements at sea level.
When do chemists reach for this conversion?
Any time a gauge reading has to drop into PV = nRT with R in L·atm/(mol·K). Regulators show psi; the calculation wants atm. The conversion is one of the most common unit-translation steps in practical gas-law work.