Framing Calculator
Studs = wall length ÷ spacing, rounded down, plus one, then 3 per corner, 2 per partition junction and 4 per opening. A 40 ft wall at 16 in on centre with 4 corners and 2 openings needs 31 + 20 = 51 studs, 57 with 10% waste, and 120 ft of plate. For board totals, use the Lumber Calculator.
How it's calculated: Field studs = ⌊length ÷ spacing⌋ + 1; extra studs = corners × 3 + partitions × 2 + openings × 4; plate stock = length × (1 bottom + 1 or 2 top plates).
Result appears here
Fill in the fields and press Calculate.
Formula, calculation, assumptions and sources
Field studs = ⌊ wall length ÷ spacing ⌋ + 1
Extra studs = corners × 3 + partitions × 2 + openings × 4
Plate stock = wall length × (1 bottom + 1 or 2 top plates)
Run the calculation to see each step with your own numbers.
40 ft wall, 8 ft high, 16 in o.c., double top plate, 4 corners, 0 partitions, 2 openings, 10% waste.
Field studs = ⌊480 ÷ 16⌋ + 1 = 31
Extra = 4×3 + 0 + 2×4 = 20 → total 51 → order 57 with 10%
Plate stock = 40 × 3 = 120 lineal ft
- Standard platform framing: field studs at the chosen spacing plus one to close each end.
- 3 studs per corner, 2 per partition T, and 4 per opening (2 king + 2 jack) — cripples and sills are covered by the waste allowance. Wide openings need more.
- Header lumber for openings is sized separately — see the Door Header Size and Wood Beam Span calculators.
- Plate stock is the total lineal length; buy it in 8–16 ft pieces and stagger the joints.
- 16 or 24 inch stud spacing?
- 16 in o.c. is the default for 2x4 and 2x6 walls. 24 in o.c. ('advanced framing') is code-permitted for many 2x6 walls and uses ~30% less stud lumber, but needs aligned floor/roof framing and thicker sheathing or drywall to avoid waviness.
- Does this size the headers?
- No. The opening count only adds the king and jack studs. Size the header itself from a span table or the Door Header Size / Wood Beam Span calculators.
- How many studs for a 20 ft wall at 16 inches on center?
- 16 field studs: 240 in ÷ 16 in = 15, plus one to close the end. Add 3 per corner, 2 per partition junction and 4 per door or window, then your waste allowance.
- Does the stud count include cripples, sills and blocking?
- No. Cripples, sills and blocking are left to the waste allowance, and each opening adds only its king and jack studs. Wide openings need more, and headers are sized separately.
- How much plate stock does a wall need?
- Three times the wall length with a double top plate — one bottom plate plus two top plates — or twice the length with a single top plate. A 20 ft wall needs 60 ft of plate stock with a double top plate.
Framing layout
IRC Chapter 6 / APA 'Advanced Framing' and standard framing-contractor take-off practice (field members on-centre + one; 3-stud corners; king/jack studs at openings). Standard counting; no empirical constant.
Framing layout — reference
About the Framing Calculator
The Framing Calculator produces a stud-wall take-off — field studs at your chosen spacing, the extra studs for corners, partition intersections and openings, and the lineal feet of plate stock — from the wall length and height. It counts the framing members; it does not size the headers over openings (use the Door Header Size or Wood Beam Span calculators) and it assumes standard platform framing.
What you enter
- Total wall length
- Wall height — Stud length is roughly this minus the plate thickness — precut studs suit 8, 9 and 10 ft walls.
- Stud spacing
- Top plate
- Corners — ≈ 3 studs each (a 3-stud corner).
- Interior partition intersections — ≈ 2 extra studs each (a T-intersection).
- Door / window openings — ≈ 2 king + 2 jack studs each, plus cripples; counted as 4 studs per opening.
- Waste allowance — Default 10%. Adjust to your own allowance — the exact figure is always shown too.
What you get back
- Field studs — the exact result of the calculation.
- Corner + partition + opening studs — the exact result of the calculation.
- Total studs — shown as the exact figure and, separately, a recommended figure with your waste allowance added.
- Plate stock (lineal) — One bottom plate + top plate(s), same length as the wall each.
The formula, a worked example, the assumptions behind it and the sources are shown in full below the calculator.
Related calculators
- Lumber Calculator — Lineal feet and piece count of dimensional lumber for a job.
- Door Header Size Calculator — Header size estimate for a door or window opening — an estimate, not an engineering design.
- Floor Joist Calculator — Floor joist count and a span estimate — an estimate, not an engineering design.
- Drywall Calculator — Drywall sheets, screws, mud and tape for a room.
- Wood Beam Span Calculator — Allowable span estimate for a sawn-lumber beam under a uniform load — an estimate, not an engineering design.
Part of the Framing calculators.