Slenderness Ratio Calculator

Find a column's slenderness ratio.

Effective length factor

Column length

Radius of gyration

Slenderness ratio 120

Formula: λ = K·L ÷ r

Step-by-step with your numbers:

1. Values used:

2. Effective length factor = 1

3. Column length = 3,000

4. Radius of gyration = 25

6. Effective length factor x Column length = 1 x 3,000 = 3,000

7. Slenderness ratio = (Effective length factor x Column length) / Radius of gyration = 3,000 / 25 = 120

Did we solve your problem today?

Slenderness ratio indicates whether a column will fail by buckling or crushing.

The math behind it

λ = K·L ÷ r, where r is the radius of gyration. High λ means a slender column prone to buckling.

K 1, 3000 mm, r 25 mm → λ = 120.

What's a 'long' column?

Roughly λ above 100–120, where Euler buckling governs.