Pressure
psftopsi
Convert pounds-force per square foot (psf) to pounds-force per square inch (psi).
Factor1 psf = 0.006944444 psi
Converter
psf
Accepts numbers or expressions, e.g. 150 + 14.7
Result
psi
Rendered to 6 significant figures.
Formula
Formula
psi = psf × 0.006944444
Multiply any value in pounds-force per square foot by 0.006944444 to obtain the value in pounds-force per square inch.
Worked example
Convert 1000 psf to psi.
- 01Start with 1000 psf.
- 02Multiply by the conversion factor: 1000 × 0.006944444 = 6.94444 psi.
Result1000 psf = 6.94444 psi
Conversion table
| psf | psi |
|---|---|
| 1 | 0.0069444 |
| 2 | 0.013889 |
| 5 | 0.034722 |
| 10 | 0.069444 |
| 20 | 0.13889 |
| 50 | 0.34722 |
| 100 | 0.69444 |
| 200 | 1.3889 |
| 500 | 3.4722 |
| 1000 | 6.9444 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from psf to psi?
1 psf equals 0.006944444 psi. To convert, multiply the value in pounds-force per square foot by 0.006944444.
How do I convert 1 psf to psi?
1 psf = 0.00694444 psi. For any value, multiply by 0.006944444.
How do I convert psi back to psf?
Divide by the same factor — or equivalently, multiply by 144. So 1 psi = 144 psf.
When would I need to convert pound-force per square foot to pound-force per square inch?
Pressure conversions between psf and psi are common when working with mixed-vendor instrumentation, when piping codes use different units to process datasheets, or when converting field readings into SI for hydraulic calculations.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).