What this calculator does
Studs in a timber-framed wall sit at a fixed spacing measured centre to centre, most commonly 450 or 600 millimetres. The count is not simply the wall length divided by the spacing: an extra stud is needed to close the final bay, and openings and corners each need additional framing beyond the regular pattern.
This calculator works out the common studs from the length and spacing, adds allowances for the openings and corners you specify, and gives the plate timber needed for the top and bottom of the wall.
The formula
Divide the wall length by the spacing and round down, then add one for the stud that closes the last bay. Two extra studs are added for each opening, covering the jack and king studs on each side, and one per corner or wall junction. Plate timber is the wall length multiplied by the number of plates.
| Term | Meaning |
|---|---|
| Stud spacing | The centre to centre distance between studs, typically 450 or 600 millimetres in domestic framing. |
| Common stud | A full-height stud in the regular spacing pattern, as opposed to the extra framing around an opening. |
| Plate | The horizontal timber running along the top and bottom of the wall that the studs fix into. |
The inputs explained
| Field | What to enter |
|---|---|
| Wall length (m) | The overall length of the wall in metres. |
| Stud spacing (centres) (mm) | The stud spacing in millimetres, measured centre to centre. |
| Door and window openings | How many door and window openings the wall contains. Each adds two studs as an allowance. |
| Corners and junctions | How many corners or wall junctions this wall forms, each of which needs an extra stud. |
| Plates (top and bottom) | Two plates covers a single top plate; three covers a doubled top plate where the construction calls for it. |
When to use it
Pricing a wall before ordering
A stud count and plate length together give the timber quantity, which is the main material figure needed for a quote.
Comparing spacings
Moving from 450 to 600 millimetre centres cuts the stud count noticeably, though the spacing that is allowed depends on the structural requirements and the lining material.
Checking a supplier list
Recalculating the count independently is a quick way to see whether a quoted quantity allowed for openings and corners or just the regular pattern.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How does stud count change with spacing on a 6 metre wall?
The same wall framed at a range of common stud spacings.
Questions
Why add one stud to the division?
Spacing describes the gaps between studs, and a run of gaps always has one more stud than gaps: a wall with two bays has three studs. Dividing alone counts the bays and misses the closing stud.
Is two extra studs per opening always right?
It is a working allowance rather than a rule. A typical opening needs a jack and a king stud on each side, and wide openings or a heavy lintel can need more. Treat the figure as a starting point and check the specific detail being built.
What spacing should I use?
That is set by the structural requirements, the lining material and the local building code, not by preference. Common domestic framing uses 450 or 600 millimetre centres, but the applicable standard governs.
Does this include noggings or bracing?
No. It covers vertical studs and the plate timber only. Noggings, bracing and lintels are additional and depend on the wall height and the construction detail.
For the lining that goes over the frame, see the plasterboard calculator. For a beam over an opening, see the timber beam span calculator.