Can 2×10 be used for stair stringers?
If you are building code compliant stairs the tread dimension (depth or front to back) needs to be 10″ or more. The rise needs to be 7 1/4″ to not more than 8″. I have never tried to make a 2×10 work but I’m pretty sure that a 2×8 would not work unless you are building something more like a ladder for loft access.
Pressure-treated or cedar 2×10 or 2×12 can be used depending on the depth of the cut-outs you’ll be using.