Kilopascals to PSI
Convert kilopascals (kPa) to psi (psi). Both measure force per area, and the conversion comes up in weather, automotive, diving work.
The Formula
``
psi = kilopascals × 0.14503773773
kilopascals = psi × 6.89475729317
`
One kilopascal is 0.145038 psi, and one psi is 6.8948 kilopascals.
Conversion Table
| 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 |
The Other Direction
| 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 |
What Each Unit Is
Kilopascals (kPa) — 1,000 pascals. The practical metric working unit for tyre and industrial pressures.
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.
A Sense of Scale
Car tyres run at 220–250 kPa- Atmospheric pressure is 101.3 kPa
- Car tyres run at 32–35 psi
- Household water is 40–60 psi
Doing It in Your Head
Divide by 7. That is off by 1.50% — close enough to judge a
distance, a weight or a price, and not close enough to sign off on a drawing.
Exact Mental shortcut 1.4504 psi 1.4286 psi 14.5038 psi 14.2857 psi
Precision
The factor 0.14503773773 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 kilopascalToPsi = (value) => value * 0.14503773773;
``
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 kPa with the factor truncated at each decimal place:
| Decimals kept | Factor | 137 kPa becomes | Error |
|---|---|---|---|
| 0 | 0 | 0 | 100.0000% |
| 1 | 0.1 | 13.7 | 31.0524% |
| 2 | 0.15 | 20.55 | 3.4214% |
| 3 | 0.145 | 19.865 | 0.0260% |
| 4 | 0.145 | 19.865 | 0.0260% |
The right number of significant figures is set by your input, not by the converter. If you measured kilopascals to three significant figures, the answer in psi is only good to three — writing more digits claims precision the measurement never had.