Stud Calculator: How Many Studs Do I Need?
Enter the walls you are framing and the spacing you are working to. You will get the stud count, the extra studs corners and openings need, and the plate lumber to go with them.
Walls and spacing
Enter each wall separately — every wall needs its own closing stud.
This is a material estimate for a straight framed wall. It says nothing about whether a wall is load-bearing, what a header should be, or what your local code requires — those are questions for a professional, not a calculator.
How many studs do I need?
Divide the wall length by the spacing and add one, because a wall ends with a stud as well as starting with one. Then add the extras: a corner needs more than one stud to give both walls something to fix to, and an opening needs king and jack studs on each side.
Each wall is counted separately rather than summing the lengths first, because each one needs its own closing stud. Adding two 12 ft walls as a single 24 ft wall would leave you one stud short.
Spacing
| Spacing | Notes |
|---|---|
| 16 in on centre | The common interior and exterior wall spacing |
| 24 in on centre | Used where the design and code allow it |
Which spacing is appropriate is a design and code question, not a preference. Sheet materials are sized around 16 and 24 inch centres, so both keep drywall and sheathing joints landing on framing.
Plates
A conventional wall has a single bottom plate and a doubled top plate — 3 plates, so 3 times the wall length in lumber. A wall built into an existing structure may take fewer.
Plate lumber is quoted here as linear feet rather than a piece count, because plates are cut to the wall and joined over studs rather than bought to a fixed length.
What this does not cover
Headers, blocking, fire stops, fasteners, sheathing and anything structural are outside this calculator. Beam sizing, load paths and code compliance are deliberately out of scope for this whole site — they are the places where a confident-looking number does real harm.
If you are removing or altering a wall that might be carrying load, that is a question for a structural engineer before it is a question about lumber.
Common mistakes
- Summing wall lengths instead of counting each wall separately.
- Forgetting the closing stud at the end of a run.
- Counting one stud per corner rather than the three a corner assembly needs.
- Treating a material count as a structural design.
Insulating and boarding after?
Work out the cavity area for the walls you are about to frame.
Open the Insulation Calculator →