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Atmospheres (atm) to PSI Conversion Chart

Reference chart converting standard atmospheres (atm) to PSI. Covers 0.1–1,000 atm — for diving, scientific, industrial, and engineering pressure calculations.

For a custom value not in this chart, use the interactive Atmosphere to Pounds per Square Inch converter.

Atmosphere (atm)Pounds per Square Inch (psi)
0.1 atm1.46959 psi
½ atm7.34797 psi
1 atm14.6959 psi
1.5 atm22.0439 psi
2 atm29.3919 psi
3 atm44.0878 psi
5 atm73.4797 psi
10 atm146.959 psi
15 atm220.439 psi
20 atm293.919 psi
25 atm367.399 psi
30 atm440.878 psi
40 atm587.838 psi
50 atm734.797 psi
75 atm1102.2 psi
100 atm1469.59 psi
200 atm2939.19 psi
300 atm4408.78 psi
500 atm7347.97 psi
1000 atm14695.9 psi

Conversion Formula

PSI = atm × 14.6959
atm = PSI ÷ 14.6959  (= PSI × 0.068046)

1 atm = 101,325 Pa = 14.696 PSI = 1.01325 bar = 760 mmHg

Diving depth reference (salt water at 1.025 g/cm³):
  Sea level = 1 atm = 14.70 PSI (gauge = 0 PSI)
  10 m depth  = 2 atm abs = 14.70 PSI gauge
  20 m depth  = 3 atm abs = 29.39 PSI gauge
  30 m depth  = 4 atm abs = 44.09 PSI gauge  (max rec. recreational)
  40 m depth  = 5 atm abs = 58.78 PSI gauge

Industrial reference:
  10 atm = 147.0 PSI  (high-pressure autoclave)
 100 atm = 1,470 PSI  (deep-sea equipment)

Frequently Asked Questions

How many PSI is 1 atmosphere?

1 standard atmosphere (atm) = 14.696 PSI = 101.325 kPa = 1.01325 bar. This is the standard sea-level atmospheric pressure used as a reference in all pressure calculations.

How many atmospheres is 100 PSI?

100 PSI ÷ 14.696 = 6.804 atm. A workshop air compressor delivering 100 PSI operates at about 6.8 times atmospheric pressure.

How does pressure increase with diving depth?

In seawater, pressure increases by approximately 1 atm (14.70 PSI) for every 10 meters of depth. At 10 m depth: 2 atm absolute (1 atm from air + 1 from water). At 30 m: 4 atm absolute — the maximum recommended depth for recreational scuba divers.

What is the difference between absolute pressure and gauge pressure?

Absolute pressure (psia) measures pressure relative to a perfect vacuum (0 pressure). Gauge pressure (psig) measures pressure above atmospheric (relative to ambient air). A tire reading 35 PSI gauge = 35 + 14.696 = 49.7 psia absolute. At sea level, absolute = gauge + 14.696. In scientific contexts, always specify which type.

What is a standard atmosphere used for?

The standard atmosphere (atm) is used as a reference pressure in chemistry (STP conditions), diving (depth-pressure calculations), and atmospheric science. It equals exactly 101,325 pascals by SI definition. In everyday engineering, bar is often preferred because it is a round number close to 1 atm (1 bar = 0.987 atm).

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All conversion values are calculated using internationally recognized conversion factors. Results are provided for general informational purposes — verify critical values independently. Read our full disclaimer.