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Stud framing calculator
Industry standard
Result
Studs
Plate lumber
Region
Waste
Prices: national avg · Jun 2026 · sources
DiagramUpdates as you type

Estimate the number of studs and linear feet of plate lumber for a wall from its length and stud spacing.

Formula

studs = (floor(wall_in ÷ spacing) + 1) × (1 + waste)

Method & sources
Formula basisIndustry on-center framing
How we calculateStuds = wall length ÷ on-center spacing + 1, plus top/bottom plates and opening allowances.
Formula verified against the published standard above. Method last reviewed June 2026. Estimates are for planning — confirm against supplier quotes.

How it works

Studs are spaced 16″ or 24″ on center. Count is the wall length divided by spacing, plus one, plus extra for corners and openings.

Plates

A standard wall has one bottom plate and a double top plate — three times the wall length in plate lumber.

Worked example

Studs for a 24 ft wall at 16 inches on center

A 24 ft wall is 288 inches. At 16-inch on-center spacing: 288 ÷ 16 = 18, plus 1 for the end stud = 19 studs for the field. Then add extra for each corner (typically 2-3 studs per corner), each opening (king and jack studs plus cripples), and any partition intersections. The 15% waste factor roughly covers these extras on a simple wall.

For plates, a standard wall has a single bottom plate and a double top plate — three runs of 24 ft, or 72 linear feet of plate stock.

What affects your result

Common mistakes to avoid

Where the numbers come from

16″ on center is the common residential spacing. The 15% waste covers corners, openings, and blocking.

Plates, corners, and openings

The field-stud count is only the start. Add the plates — one bottom plate and a double top plate means three plate-lengths of stock. Corners and wall intersections need extra studs to form drywall backing, typically two or three per corner. Every door and window adds king studs, jack studs, a header, and cripple studs above and below.

Spacing and stud grade

Standard spacing is 16 inches on-center for load-bearing walls; 24-inch on-center (advanced framing) uses fewer studs where the engineering allows. Buy a little extra stud stock — every bundle includes a few studs too bowed or split to use full-length, which still work as blocking and cripples. Add 10–15% waste.

Frequently asked questions

How many studs for a 16 ft wall?

About 13 at 16″ on center, before extras for corners and openings.

How many studs do I need for a wall?

Divide the wall length in inches by the spacing (16 or 24 inches) and add one, then add extra studs at corners, intersections, and openings, plus a 10–15% waste allowance.

How much plate lumber do I need?

A standard wall has one bottom plate and a double top plate, so plan three times the wall length in plate stock.

What is the difference between 16 and 24 inch on-center spacing?

16 inches on-center is standard for load-bearing walls; 24 inches on-center (advanced framing) uses fewer studs and is allowed in many non-bearing and engineered situations.

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