How to Convert Atmospheres to Kilopascals (atm to kPa)
Pressure conversions are used for tyre pressure (psi or bar), blood pressure readings in mmHg and weather maps in millibars. This guide shows how to convert atmospheres into kilopascals by hand, with examples and a quick-reference table.
The conversion
To convert atmospheres to kilopascals, multiply the value by 101.325. To go the other way, divide by the same number (or multiply by 0.0098692327). For a quick estimate, multiply by about 100.
Kilopascals = atmospheres × 101.325
Worked examples
- 3 atm = 303.975 kPa
- 12.5 atm = 1,266.56 kPa
- 75 atm = 7,599.38 kPa
Atmospheres to Kilopascals table
| Atmospheres | Kilopascals |
|---|---|
| 1 atm | 101.325 kPa |
| 2 atm | 202.65 kPa |
| 5 atm | 506.625 kPa |
| 10 atm | 1,013.25 kPa |
| 20 atm | 2,026.5 kPa |
| 25 atm | 2,533.12 kPa |
| 50 atm | 5,066.25 kPa |
| 100 atm | 10,132.5 kPa |
| 250 atm | 25,331.25 kPa |
| 500 atm | 50,662.5 kPa |
| 1,000 atm | 101,325 kPa |
Common questions
Is atm to kPa exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Kilopascals to Atmospheres converter.
Mistakes to avoid
Rounding the factor too early
Using 3 instead of 3.28 for feet per metre introduces an error of almost 9% before you have started.
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
Dropping the units
A bare number without a unit is easy to misread later. Always write the unit with the result.
Background
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
Writing the units next to every number while you work is the simplest way to avoid mistakes. If the units do not cancel to leave the one you want, the calculation is set up wrongly.
For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.
For any value, use the Atmospheres to Kilopascals Converter or browse all pressure converters.
Run your own numbers: Atmospheres to Kilopascals Converter