Convert Kilopounds per Square Inch to Standard Atmospheres
Convert Kilopounds per Square Inch (ksi) to Standard Atmospheres (atm) instantly and accurately.
Conversion Formula
atm = ksi × 68.04596391
About Kilopounds per Square Inch
One ksi (kilopound per square inch) = 1,000 psi ≈ 6.895 MPa - the standard engineering stress unit in the US. ASTM A36 structural steel: 36 ksi yield, 58-80 ksi tensile. ASTM A325 high-strength bolts: 92 ksi proof load. AISC steel construction tables, FAA/MIL-SPEC aerospace allowables, and ASME Section VIII pressure vessel design all use ksi. Fracture toughness (K_IC) for steels: 50-200 ksi·√in. Convenient because it keeps large structural stresses as manageable 3-digit numbers. 1 ksi = 6.895 MPa.
About Standard Atmospheres
The standard atmosphere (atm) = exactly 101,325 Pa - defined by the 10th CGPM (1954) as the reference air pressure at sea level. Used to define STP (0°C and 1 atm) for gas law and thermochemistry. Chemical equilibrium constants (Kp), Henry's law solubility, and thermodynamic tables are tabulated at 1 atm. ISA aviation standard: sea-level 1 atm / 15°C, pressure halving every ~5.5 km. Diving physics: +1 atm per 10 m depth (fresh water) so 30 m = 4 atm absolute. Diamond formation in Earth's mantle: ~50,000 atm. 1 atm = 101,325 Pa.
Quick Reference Table
| Kilopounds per Square Inch (ksi) | Standard Atmospheres (atm) |
|---|---|
| 1 ksi | 68.046 atm |
| 2 ksi | 136.092 atm |
| 5 ksi | 340.23 atm |
| 10 ksi | 680.46 atm |
| 25 ksi | 1701.15 atm |
| 50 ksi | 3402.3 atm |
| 100 ksi | 6804.6 atm |