I assume you are cutting from a log. I usually cut boaeds 2" thick, seal the ends and let them sit a year or two. I have an el cheapo moisture meter and check every now and then. Some woods will dry much faster than others. And, depending on the species and how it was cut, the board will twist, cup, and bend a bit. My 2" board yields a 1" to 1.75" board after planing.
I sometimes will buy 8/4 lumber and resaw to get more for my money. Of course, if you figure the time it takes to reaaw and surface the board you may not save much $$ but it is satisfying to do.