Hectopascal to Atmosphere
Convert Hectopascal to Atmosphere instantly. Free online pressure unit converter with exact formula, conversion table and FAQ.
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Formula
atmosphere = hectopascal × 0.000987
hectopascal = atmosphere × 1013.25
Conversion table
| 1 hPa | 0.000987 atm |
| 5 hPa | 0.004935 atm |
| 10 hPa | 0.009869 atm |
| 20 hPa | 0.019738 atm |
| 50 hPa | 0.049346 atm |
| 100 hPa | 0.098692 atm |
| 500 hPa | 0.493462 atm |
| 1000 hPa | 0.986923 atm |
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Frequently asked questions
What is the source unit in this conversion?
The source unit is the hectopascal (hPa). Hectopascal is 100 pascal units.
What is the destination unit in this conversion?
The destination unit is the atmosphere (atm). A standard atmosphere is exactly 101,325 pascals.
How do I convert hectopascal to atmosphere?
Multiply the hectopascal value by 0.000987. For example, 10 hPa × 0.000987 = 0.009869 atm.
Is the hectopascal to atmosphere conversion exact?
Yes. Both units are defined as fixed multiples of the pascal, the SI-derived unit of pressure, so the conversion factor follows directly from those exact definitions rather than a measured approximation.
Where is this conversion commonly used?
It's used whenever a value expressed in hectopascal needs to be compared with, or reported in, atmosphere, such as in engineering specifications, weather readings, tire pressure, or industrial and scientific work.
Can I convert atmosphere back to hectopascal?
Yes. Multiply the atmosphere value by 1013.25 to get hectopascal.
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About this conversion
This page converts hectopascal (hPa) to atmosphere (atm) within the pressure converter.
Hectopascal is 100 pascal units. A standard atmosphere is exactly 101,325 pascals.
The formula is atmosphere = hectopascal × 0.000987, based on each unit's fixed relationship to the pascal, the pressure converter's base unit.
The conversion is exact, since both units are tied to the pascal by a fixed numerical ratio rather than a measured or approximate value.
Use the calculator above for instant results, or the table below for common hectopascal values already converted to atmosphere.