How the math works
Layout studs = wall length (in) ÷ spacing, rounded down, + 1.Add 2 for corner / end backing.Add waste (10% typical).Plates = 3 × wall length (single bottom, double top).
Trade pro tips
- 24" OC (advanced framing) saves lumber but needs aligned framing and 2x6 walls in most codes.
- Count king, jack and cripple studs separately for each opening.
Frequently asked questions
How do you calculate studs for a wall?
Wall length in inches ÷ 16, round down, add 1 for layout; add 2 for corners and ~10% for waste and openings.
What does 16 on center mean?
The center of each stud is 16" from the center of the next — sheets of 4x8 drywall and sheathing break on every third stud.
Is 24" on center allowed?
Yes for many walls under the IRC (Table R602.3(5)), especially 2x6 exterior walls, if loads and finishes allow.
How long is a precut stud?
92-5/8" for 8' walls, 104-5/8" for 9', 116-5/8" for 10'.