psi to atm Converter

When to use pounds per square inch → standard atmospheres

PSI to atmospheres divides by 14.6959 (1 atm = 14.6959 psi). A 32 psi tyre is 2.18 atm of gauge pressure; 100 psi compressed air is 6.8 atm. The standard atmosphere is a fixed reference (101 325 Pa), not the fluctuating local air pressure. Atmospheres are handy for scuba rules of thumb (each 10 m of seawater adds about 1 atm) and legacy chemistry; psi is the working unit for US tyres, plumbing, and pneumatics.

Deep-sea submersible hulls and high-pressure research vessels are rated in psi by American manufacturers, but marine engineers checking depth-equivalent pressure often think in atmospheres, since roughly 1 atm is added per 10 m of seawater. A 3,000 psi hull rating corresponds to 204.1 atm, equivalent to a crush depth well past 2,000 m. Because the psi-to-atm factor carries no simple round number, engineers verifying a safety margin on an imported pressure vessel keep the exact 14.6959 factor rather than estimating, given the thin error tolerance at extreme ocean depths.

How to convert pounds per square inch to standard atmospheres

1. 1

   Take your value

   Start with your value in pounds per square inch.

2. 2

   Multiply by 0.068046

   Multiply the pound per square inch value by 0.068046. This is the exact conversion factor from pounds per square inch to standard atmospheres.

3. 3

   Read the result

   The product is your value in standard atmospheres. For example, 5 psi × 0.068046 = 0.34023 atm.

Conversion formula

The exact factor from pounds per square inch to standard atmospheres is 0.068046.

Standard atmospheres = Pounds per square inch × 0.068046

Pounds per square inch to Standard atmospheres conversion table

Fifty common reference values, hand-picked for skim utility. Use the calculator above for any value not listed.

Real-world reference

Most US passenger-car tires call for 32–35 psi. A typical bicycle tire runs 50–80 psi. In standard atmospheres, that gives you: 1 psi = 0.068046 atm, 10 psi = 0.68046 atm, 100 psi = 6.8046 atm.

Frequently asked questions

How many standard atmospheres are in 1 pound per square inch?

1 pound per square inch equals 0.068046 standard atmospheres.

How do I convert pounds per square inch to standard atmospheres?

Multiply the pound per square inch value by 0.068046. So x psi × 0.068046 = the equivalent in atm.

What is 5 pounds per square inch in standard atmospheres?

5 pounds per square inch equals 0.34023 standard atmospheres.

What is 10 pounds per square inch in standard atmospheres?

10 pounds per square inch equals 0.68046 standard atmospheres.

What is 100 pounds per square inch in standard atmospheres?

100 pounds per square inch equals 6.8046 standard atmospheres.

How do I convert back from standard atmospheres to pounds per square inch?

Multiply the standard atmosphere value by 14.6959. For example, 1 atm = 14.6959 psi.

Is the pound per square inch bigger than the standard atmosphere?

No. 1 pound per square inch is smaller than 1 standard atmosphere. It takes 14.6959 pounds per square inch to equal 1 standard atmosphere.

Are these conversion factors exact?

The factor is derived directly from the SI definitions of pound per square inch and standard atmosphere; the displayed value is rounded for readability, and the browser computes using IEEE 754 double-precision arithmetic.

About the pound per square inch and the standard atmosphere

Sources

• NIST Special Publication 811 — Guide for the Use of the International System of Units (SI)
• BIPM — SI Brochure (9th edition)
• Reverse: atm to psi
• All pressure converters