how to compare wood post to steel post
There are many variables with the steel supports 1) type of steel, 2) grade of steel, etc. and with the wood supports: 1) species, 2) grade, etc.
I’ll use A36 structural steel and SPF No.1 grade wood for comparison.
A 2 1/2” x 2 1/2” x 8’ high square structural tubing can support about 28 kips (28,000 lbs.) in axial (vertical) load.
A 4x4x8’ high wood post can support about 9 kips of axial load.
If you’re thinking of a different type of loading, please advise.