Pascals to Atmospheres Converter

Pascals to Atmospheres

Convert pascals (Pa) to atmospheres (atm). Both measure force per area, and the conversion comes up in weather, automotive, diving work.

The Formula

`` atmospheres = pascals × 0.00000986923266716 pascals = atmospheres × 101325 `

One pascal is 9.8692e-6 atmospheres, and one atmosphere is 101,325 pascals.

Conversion Table

Pascals	Atmospheres
1 Pa	9.8692e-6 atm
2 Pa	1.9738e-5 atm
5 Pa	4.9346e-5 atm
10 Pa	9.8692e-5 atm
25 Pa	2.4673e-4 atm
50 Pa	4.9346e-4 atm
100 Pa	9.8692e-4 atm
500 Pa	0.004935 atm
1,000 Pa	0.009869 atm

The Other Direction

Atmospheres	Pascals
1 atm	101,325 Pa
2 atm	202,650 Pa
5 atm	506,625 Pa
10 atm	1,013,250 Pa
25 atm	2,533,125 Pa
50 atm	5,066,250 Pa
100 atm	10,132,500 Pa
500 atm	50,662,500 Pa
1,000 atm	101,325,000 Pa

What Each Unit Is

Pascals (Pa) — one newton per square metre — the SI derived unit of pressure. Named for Blaise Pascal, who established that pressure varies with altitude.

Atmospheres (atm) — exactly 101,325 pascals, by definition. The mean air pressure at sea level, adopted as a reference standard.

A Sense of Scale

• Atmospheric pressure is 101,325 Pa
• A pascal is a very small unit
• Pressure doubles at 10 m underwater
• Everest’s summit is about 0.33 atm

Precision

The factor 0.00000986923266716 is exact by international agreement, not a rounded approximation. Any imprecision in a result comes from your input, not the conversion.

In Code

`javascript const pascalToAtmosphere = (value) => value * 0.00000986923266716; ``

Where This Conversion Comes Up

• Weather
• Automotive
• Diving
• Aviation
• HVAC

How Many Decimals Do You Need?

Rounding the factor costs accuracy, and how much depends on the factor. Converting 137 Pa with the factor truncated at each decimal place:

Decimals kept	Factor	137 Pa becomes	Error
0	0	0	100.0000%
1	0	0	100.0000%
2	0	0	100.0000%
3	0	0	100.0000%
4	0	0	100.0000%

A rule that holds for any conversion: round once, at the end. Rounding the factor and then multiplying compounds the error through every subsequent calculation, while carrying full precision and rounding the final answer does not.

The right number of significant figures is set by your input, not by the converter. If you measured pascals to three significant figures, the answer in atmospheres is only good to three — writing more digits claims precision the measurement never had.

Other Conversions From Pascals

The same value in every other unit this converter supports for pressure:

From	To	Unit
1 Pa	0.001 kPa	Kilopascals
1 Pa	1.0000e-5 bar	Bar
1 Pa	1.4504e-4 psi	PSI
1 Pa	0.00750062 mmHg	mmHg

Chaining conversions works — pascals to metres to feet gives the same answer as pascals to feet — but each step rounds, so a chain of three conversions carries three roundings. Convert directly where a direct factor exists.