Can I Use a 2X10 for Stair Stringer?

It is acceptable and within building code guidelines to use either 2×10 or 2×12 dimensional lumber to create a set of stairs; however, a stair stringer should not be less than 3.5 inches wide at its narrowest point to provide adequate strength for the load the stairs will be supporting.

What size Stringer do I need for stairs?

Stringers should always be cut from 2x12s. Notching smaller stock doesn't leave enough wood to safely carry the loads of a stair. When ordering stringers, allow about 14 inches of stringer length for each step.

Can I use 2x12 for stair stringers?

I use 2x12 if there is not an issue with head room below the stairs. Makes a strong set of stairs but it seems the majority of framers around here use 2x10.