This framing calculator turns a wall length and height into a lumber list: layout studs at 16" or 24" on center, king and jack studs for every door and window, extra studs at corners and wall intersections, single bottom and double top plates, two-ply headers, and an estimate of 16d nails from the IRC fastener schedule. Openings can be mixed and matched, and the waste allowance rounds up to whole studs.
Once the wall is framed, the drywall calculator and insulation calculator cover the next steps, and the board foot calculator prices the lumber if your yard sells by the board foot. Building outside? The fence calculator counts posts, rails, and pickets for a fence line.
Frequently asked questions
How many studs do I need for a wall?
Divide the wall length in inches by the stud spacing (16 or 24 inches on center), round up, and add one for the end. A 12-foot wall at 16" o.c. needs 144 ÷ 16 = 9, plus 1 = 10 studs. Then add 2 per corner, 2 per wall intersection where a partition tees in, and 4 per door or window (two king studs and two jack studs). Finish with a 10–15% waste allowance for warped or split pieces. The calculator does each step and shows the breakdown.
Should I frame at 16 or 24 inches on center?
16" on center is the default for most load-bearing walls and gives stiffer walls for hanging cabinets and drywall. 24" spacing, part of "advanced framing," uses fewer studs and leaves more room for insulation, and is allowed by the IRC for many walls — but it depends on stud size, wall height, and how many floors the wall carries (IRC Table R602.3(5)). Drywall and sheathing thickness can also limit spacing, so confirm with your plans or building department. When in doubt, frame at 16".
What are king, jack, and cripple studs?
At every door or window, a full-height king stud runs from plate to plate on each side. A shorter jack (trimmer) stud nails to each king and carries the header. Cripples are short studs that fill the gap below a window sill and above the header. Because the regular layout studs that would fall inside the opening get cut into cripples, this calculator counts cripples as pieces from offcuts rather than extra purchases. Wide openings or heavy headers may need doubled jack studs — the header span table lists how many jacks each span requires.
How much plate lumber do I need?
A standard wall has one bottom (sole) plate and a double top plate, as required for most bearing walls by IRC R602.3.2 — three times the wall length in linear feet. The second top plate should overlap the first at corners and splices by at least 24 inches, so stagger the joints. The calculator reports linear feet and the number of pieces for the plate stock length you pick, counting each of the three rows separately so the splices can be offset. Pressure-treated lumber is required for a bottom plate that sits directly on concrete.
Does this size my headers?
No. It reports header lumber as two plies at the rough-opening width plus 3 inches (1½" of bearing on a jack at each end). The header depth — 2×6, 2×8, 2×10, 2×12 or engineered lumber — depends on the span, the loads above, snow load, and building width, and must come from IRC Table R602.7(1) or an engineer. Non-bearing interior walls can often use a single flat 2× header; check your local code. Engineered LVL headers are sized from the manufacturer's span charts instead.