Drywall & Trim Calculators
Sheet goods and millwork: how many boards a room takes with the mud and tape that go with them, and how much trim a stair or a wainscot run consumes.
There are 3 calculators here: 12x12 Room Drywall Sheet Calculator (sheet count, mud, tape and screws for a room), Wainscoting Panel Calculator (panels, chair rail and baseboard for a wainscoted room), and Stair Tread & Riser Material Calculator (tread, riser and nosing counts for finishing a staircase).
They all work the same way: quantity first, then a waste allowance you can change, then a price built from verified figures and adjusted for your state. Cost is always a range rather than a single number, and every assumption behind it is printed on the page with its source and the date it was last checked.