PSI to Kilopascals
Convert psi (psi) to kilopascals (kPa). Both measure force per area, and the conversion comes up in weather, automotive, diving work.
The Formula
``
kilopascals = psi × 6.89475729317
psi = kilopascals × 0.14503773773
`
One psi is 6.8948 kilopascals, and one kilopascal is 0.145038 psi.
Conversion Table
| PSI | Kilopascals |
|---|---|
| 1 psi | 6.8948 kPa |
| 2 psi | 13.7895 kPa |
| 5 psi | 34.4738 kPa |
| 10 psi | 68.9476 kPa |
| 25 psi | 172.3689 kPa |
| 50 psi | 344.7379 kPa |
| 100 psi | 689.4757 kPa |
| 500 psi | 3,447.38 kPa |
| 1,000 psi | 6,894.76 kPa |
The Other Direction
| Kilopascals | PSI |
|---|---|
| 1 kPa | 0.145038 psi |
| 2 kPa | 0.290075 psi |
| 5 kPa | 0.725189 psi |
| 10 kPa | 1.4504 psi |
| 25 kPa | 3.6259 psi |
| 50 kPa | 7.2519 psi |
| 100 kPa | 14.5038 psi |
| 500 kPa | 72.5189 psi |
| 1,000 kPa | 145.0377 psi |
What Each Unit Is
PSI (psi) — pounds-force per square inch, equal to 6,894.76 pascals. The imperial pressure unit, still standard for US tyres, plumbing and compressed air.
Kilopascals (kPa) — 1,000 pascals. The practical metric working unit for tyre and industrial pressures.
A Sense of Scale
Car tyres run at 32–35 psi- Household water is 40–60 psi
- Car tyres run at 220–250 kPa
- Atmospheric pressure is 101.3 kPa
Doing It in Your Head
Multiply by 7. That is off by 1.53% — close enough to judge a
distance, a weight or a price, and not close enough to sign off on a drawing.
Exact Mental shortcut 68.9476 kPa 70 kPa 689.4757 kPa 700 kPa
Precision
The factor 6.89475729317 is rounded. For engineering work carry more digits than the table above, and round only at the end — rounding at each step compounds.
In Code
`javascript
const psiToKilopascal = (value) => value * 6.89475729317;
``
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 psi with the factor truncated at each decimal place:
| Decimals kept | Factor | 137 psi becomes | Error |
|---|---|---|---|
| 0 | 7 | 959 | 1.5264% |
| 1 | 6.9 | 945.3 | 0.0760% |
| 2 | 6.89 | 943.93 | 0.0690% |
| 3 | 6.895 | 944.615 | 0.0035% |
| 4 | 6.8948 | 944.588 | 0.0006% |
The right number of significant figures is set by your input, not by the converter. If you measured psi to three significant figures, the answer in kilopascals is only good to three — writing more digits claims precision the measurement never had.