Angle and Channel Properties
Properties of an equal angle or a channel, about the centroidal axes. Both are singly symmetric, so the weak axis and the centroid offset matter — which is why a channel buckles about an axis that is not where you expect.
| Thickness (mm) | Area (mm²) | Iy (×10⁶) |
|---|---|---|
| 6 | 1164 | 1.1 |
| 8 | 1536 | 1.5 |
| 10 | 1900 | 1.8 |
| 12 | 2256 | 2.1 |
| 15 | 2775 | 2.5 |
A = Σ b·t · Two legs or web plus flanges.
I = Σ(I_i + A_i·d²) · Parallel axis about the centroid.
A clear path from inputs to results.
Properties of an equal angle or a channel, about the centroidal axes. Both are singly symmetric, so the weak axis and the centroid offset matter — which is why a channel buckles about an axis that is not where you expect.
How to use
- Set shape.
- Set depth (mm).
- Set width / leg (mm).
- Set thickness (mm).
- Read the headline metrics, then check the table for the detail.
The formula
Reference: Centroidal properties for angle and channel sections.
Worked example
At the default inputs
- Shape: angle; Depth (mm): 100; Width / leg (mm): 100; Thickness (mm): 10
- 1
Area: 1900 mm² · Ix: 1.8 ×10⁶ mm⁴ · Iy: 1.8 ×10⁶ mm⁴ · Section modulus: 25 ×10³ mm³
Area: 1900 mm² · Ix: 1.8 ×10⁶ mm⁴ · Iy: 1.8 ×10⁶ mm⁴
Interpreting the result
This angle has Ix 1.8 and Iy 1.8 ×10⁶ mm⁴.
Assumptions & limitations
- Equal legs for the angle.
- Sharp corners.
Frequently asked questions
Why is the centroid offset?
An angle or channel is not symmetric, so the centroid sits toward the heavier material.
Does that affect buckling?
Yes — the member buckles about the centroidal axes, which are not where the geometry suggests.
Methodology last reviewed 2026-10-22. Results are informational and not financial or engineering advice — see our disclaimer.