psi to atmospheres

A tire gauge reads 30 psi; a scuba table thinks in atmospheres; a European spec sheet writes bars. All three describe the same inflation, and the psi-to-atm bridge is 0.06804596390987 — the exact number of atmospheres in one pound per square inch, built from the 1959 pound, the 2.54 cm inch, and the 101,325 Pa standard atmosphere. Thirty psi is 2.04 atmospheres, which is why a scuba diver at 33 feet of seawater feels about two atmospheres of pressure.

By EnginStack Engineering Team | Verified by engineers, built on NIST metrology standards About →
psi
30 atmospheres
30 psi = 2.04137892 atmospheres 30 atmospheres = 440.87846327 psi

Authority: NIST SP 811 (SI usage guide) and the 1959 International Yard and Pound Agreement. The coefficient above is a defined value — it does not come from measurement and carries no uncertainty.

psi to atmospheres

One psi is exactly 6894.757293168 Pa — the pound-force (0.45359237 kg × 9.80665 m/s²) over the square inch ((0.0254 m)²) — and one standard atmosphere is exactly 101,325 Pa, so one psi is exactly 101,325 / 6894.757293168 = 0.06804596390987 atm. The number carries eleven digits because it chains three treaty definitions. The practical uses: tire inflation, compressor discharge, pneumatic tools — all quoted in psi in America and atmospheres or bars abroad.

atmospheres = psi × 0.06804596390987
1 psi = 0.06804596390987 atmospheres — 6894.757293168 Pa ÷ 101,325 Pa
The factor is exact from the pound, inch, and standard atmosphere definitions.

Common psi to atmospheres Conversions

psiatmospheresContext
14.7 psi1.00 atmStandard sea-level atmospheric pressure.
30 psi2.04 atmA typical car tire inflation.
100 psi6.80 atmA pneumatic tool supply.
150 psi10.2 atmA heavy truck tire.
2,900 psi197 atmA scuba cylinder's rated pressure.

Engineering Context

The atmospheres to psi page inverts this factor. In the pressure hub, psi to kPa and psi to bar carry the same psi chain, and atm to Pa holds the 101,325 Pa anchor. The pound-force inside psi ties this page to the force family — psi literally means pound-force per square inch.

More: atm to psi · psi to kPa · psi to bar · Pressure Hub

Related Unit Converters

Atm To Psi Psi To Kpa Psi To Bar Pressure Converters

Frequently Asked Questions

How many atmospheres is 30 psi?

Exactly 2.0414 atmospheres. 30 psi × 0.06804596390987 = 2.0414 atm — the same pressure a scuba diver feels at about 34 feet of seawater.

What does psi stand for?

Pounds per square inch — more precisely, pound-force per square inch: the force exerted by one pound under standard gravity on a one-inch-square area. That definition is why psi converts to pascals through the pound and inch definitions.

How do I convert psi to atm quickly?

Divide psi by 14.696 for a good estimate — since 1 atm = 14.6959 psi, dividing by 14.7 is within 0.03%. For exact work use the full factor on this page, or divide by 14.6959487755.