Stud Calculator
A stud wall gets one stud every 16 or 24 inches, plus one to close the far end. Enter the wall length and spacing for the base stud count and the plate lumber.
Studs
16studs
- Plate lumber (1 bottom + 2 top)
- 60 linear ft
Stud counts are material estimates for a straight wall run — not a structural or code design. Spacing, headers, fasteners, and load paths must follow your plans and local building code.
How it’s calculated
Studs = ⌈ wall length in inches ÷ on-center spacing ⌉ + 1 — round the bays up so a partial last bay still gets its end stud, then add 1 for the starting stud. Plate lumber is the wall length times the number of plates (a single bottom plate plus a doubled top plate = 3 lengths). This is the base count for a straight run; corners, T-intersections, and openings add more.
Worked example
A 20 ft wall at 16 inches on-center: ⌈240 ÷ 16⌉ + 1 = 15 + 1 = 16 studs (plate lumber 20 × 3 = 60 ft). A 21 ft wall: ⌈252 ÷ 16⌉ + 1 = 16 + 1 = 17 studs — the short last bay still needs its end stud (plate 63 ft).
FAQs
- Should studs be 16 or 24 inches on center?
- 16-inch spacing is the residential default; 24-inch ('advanced framing') uses less lumber and is permitted for many load-bearing walls under the IRC, depending on the loads and stud size. It's code-dependent — follow your plans and local code.
- Does this count corner and opening studs?
- No — it's the base count for a straight run. Add studs for each corner and T-intersection, plus the king, jack, and cripple studs around every door and window. Those depend on your layout.
- How much plate lumber do I need?
- This assumes a single bottom plate and a doubled top plate — three times the wall length. If you're using a single top plate, use two times the length instead.
Sources
- Stud count = ceil(length_in ÷ spacing) + 1 (standard framing layout; a partial last bay still gets its end stud). Plate lumber = wall length × plate count (single bottom + double top = 3). Corner and opening framing is layout-dependent and not included.