JavaScript is off. Reference tables, cheat sheets and guides below are fully readable. The calculators, search and navigation need JavaScript — everything still runs in your browser, nothing is sent anywhere. Browse all tools

Stress Concentration Kt

Closed-form cases: small hole in a wide plate (Kt = 3, exact), elliptical hole Kt = 1 + 2a/b (Inglis), and a central hole in a finite-width plate (Heywood approximation).

Calculator

Case

—

Kt is geometric (elastic); fatigue notch factor Kf ≤ Kt. A helper, not a substitute for engineering judgment.