1 psi = 0.144 ksf, so ksf = psi × 0.144. (1 ksf = 1 kip/ft² = 1,000 lbf / 144 in² = 6.944 psi.)
| psi | ksf |
|---|---|
| 1 | 0.144 |
| 2 | 0.288 |
| 5 | 0.72 |
| 10 | 1.44 |
| 50 | 7.2 |
| 100 | 14.4 |
Multiply psi by 0.144 (144 in² per ft², divided by 1,000 lbf per kip). Example: 50 psi = 7.2 ksf.
ksf means kips per square foot (kip/ft²). 1 ksf = 1,000 lbf/ft² = 6.944 psi, and it is common for soil bearing pressure.
1 ksf = 1,000/144 = 6.944 psi.