Wall framing calculator: studs, plates and headers

Enter the wall length and height, the stud spacing, the corners and the openings. Get the stud count and cut length, plate footage in the stock length you buy, a header size from the span table with its jack studs, and the sheathing sheets.

12 to 24 in.Stud spacing

4 load casesHeader spans and jack studs

FreeNo email, no sign-up

Studs

24 ft of wall at 16 in. on center

72 ftPlates

2-2x6Header

6 sheetsSheathing

A take-off, not a design. Header sizes and stud spacing follow the code your jurisdiction adopted and the inspector.

Free. Your numbers become an estimate you can send from your phone.

How we got this

Layout studs24 ft × 12 ÷ 16 in. = 18, rounded up, + 1 for the end = 19The studs that land in a door or window are cut down into cripples above the header and below the sill, so they stay in the count.
Corners2 × 2 = 4 studsA three-stud corner is the conventional way (BSI-030). The layout already counts one stud at the corner.
Openings2 × (2 king studs + 2 × 1 jack) = 8 studsKing studs run full height beside the jacks. The jacks under each end of the header come from the header table (NC OSFM Table R602.7(1), footnote d); where it says one, a framing anchor is permitted instead.
Studs19 + 4 + 8 = 31 2x4 studs, cut to 7 ft 7 1/2 in.
Plates24 ft × 3 (bottom plate and a double top plate) = 72 ft, or 6 pieces at 12 ftConventional framing uses a double top plate (BSI-030).
Header2-2x6 spans up to 4 ft 2 in. for roof and ceiling only at 30 psf, 28 ft wide; cut 3 ft 3 in. long, 2 pieces per openingSpans for No. 2 southern pine from the NC OSFM supplemental Table R602.7(1). Other species have their own spans in IRC Table R602.7(1); your local code governs.
Sheathing192 sq ft ÷ 32 = 6 sheets of 4 × 8Openings are left in: their cut-outs are mostly waste.

Material	Quantity	Detail
2x4 studs, 7 ft 7 1/2 in.	31	19 layout, 4 corner, 8 king and jack
2x4 plates	6 × 12 ft	72 linear ft
Header 2-2x6	4 pieces of 2x6	3 ft 3 in. each, 13 linear ft
Wall sheathing, 4 × 8	6	Gross wall area

Sources: NC Office of the State Fire Marshal, Supplemental Table R602.7(1), header spans for No. 2 southern pine; Building Science Insights BSI-030, Advanced Framing (Building America Solution Center); Building America Solution Center, Advanced framing insulated corners; NIST Voluntary Product Standard PS 20-10, American Softwood Lumber Standard (board measure, Table 3 dressed sizes). Checked 2026-10-08.

Add this calculator to your websiteFree. Paste the code into any page builder that takes HTML. It fits its own height and works on phones.

<iframe src="https://www.koira.ai/embed/tools/framing-calculator" title="Framing calculator" width="100%" height="900" style="width:100%;max-width:100%;height:900px;border:0;display:block" loading="lazy" allow="clipboard-write" data-koira-tool="framing-calculator"></iframe>
<p style="margin:6px 0 0;font-size:13px"><a href="https://www.koira.ai/tools/framing-calculator" rel="noopener">Free calculator by Koira</a></p>
<script>(function(){if(window.__koiraTools)return;window.__koiraTools=1;var ok=["https://www.koira.ai","https://koira.ai"];addEventListener("message",function(e){var d=e.data;if(!d||d.type!=="koira:tool-height"||ok.indexOf(e.origin)<0)return;var f=document.querySelectorAll("iframe[data-koira-tool]");for(var i=0;i<f.length;i++)if(f[i].contentWindow===e.source)f[i].style.height=Math.max(200,Math.min(8000,Math.ceil(+d.height||0)))+"px";});})();</script>

Key takeaways

Layout studs = wall length in inches ÷ spacing, rounded up, plus one. A 24 ft wall at 16 in. on center takes 19 before corners and openings.
Add 2 studs per corner for a three-stud corner (1 for a two-stud corner), and 2 king studs plus the jack studs the header needs for every door and window.
Plates are the wall length times 3 with a double top plate. Headers come from a span table by what the wall holds up, the snow load and the building width.

How many studs do I need for a wall

Start with the layout. Studs sit at a fixed spacing from one end of the wall, with one more at the far end:

Layout studs = wall length (ft) × 12 ÷ spacing (in.), rounded up, + 1

Then add the extras that the layout does not cover:

Corners. Conventional framing builds a corner from three studs (BSI-030 describes it as the standard). The layout already put one at the end of the wall, so each corner adds two. A two-stud corner with drywall clips, the advanced framing detail, adds one and leaves room for insulation.
Doors and windows. Each opening gets a king stud on each side, running the full height, and one or more jack studs under each end of the header. The header table says how many jacks.
Cripples. The short studs above the header and below a window sill. The calculator leaves the layout studs that land in an opening in the count: they get cut down into cripples.

Wall length	Layout studs at 16 in.	Layout studs at 24 in.
8 ft	7	5
12 ft	10	7
16 ft	13	9
20 ft	16	11
24 ft	19	13
32 ft	25	17
40 ft	31	21

Blocking, backing for cabinets and fixtures, and studs where interior walls meet the outside wall are extra. Count them from the plan, or keep a few spare studs on the truck.

Plates and stud length

A wall has a bottom plate (also called the sole plate) and, in conventional framing, a double top plate. That is three times the wall length in plate stock. The calculator turns the footage into pieces of the length you buy, so a 24 ft wall with a double top plate is 72 ft, or 6 pieces of 12 ft.

A single top plate saves a third of the plate stock, but it is not a free choice. It needs in-line framing, where the joists, rafters or trusses sit right over the studs, and the plate joints have to be tied with a metal plate or a wood splice (BSI-030). Check that your design, your code and your inspector accept it before you plan on it. It also changes the stud length: the studs have to be 1 1/2 in. longer for the same wall height.

Stud cut length. The stud is the wall height less the plates. Each plate is a 2x, which is 1 1/2 in. thick dressed (American Softwood Lumber Standard, PS 20). So for an 8 ft wall with three plates, the stud is 96 − 4 1/2 = 91 1/2 in. Many yards sell precut studs sized to give a standard wall height with the drywall in place: buy those when they match your plan.

What size header do I need

A header carries the load over a door or window down to the jack studs. Its size depends on four things: the width of the opening, what the wall holds up, the ground snow load and the width of the building. The IRC gives those spans in Table R602.7(1). The free sheet the calculator uses is North Carolina's supplemental version of that table, written for No. 2 southern pine, from the NC Office of the State Fire Marshal. NC wrote it because the newer southern pine design values make some spans in the main table too long for that species.

Here are the spans for a wall holding up only the roof and ceiling, at a 30 psf ground snow load (the row to use wherever the snow load is under 30 psf and the roof live load is 20 psf or less):

Header	Building 20 ft wide	28 ft wide	36 ft wide
2-2x4	3 ft 3 in.	2 ft 10 in.	2 ft 7 in.
2-2x6	4 ft 9 in.	4 ft 2 in.	3 ft 9 in.
2-2x8	5 ft 10 in.	5 ft 2 in.	4 ft 8 in.
2-2x10	6 ft 6 in.	5 ft 9 in.	5 ft 3 in.
2-2x12	7 ft 0 in.	6 ft 3 in.	5 ft 10 in.
3-2x10	7 ft 8 in.	6 ft 10 in.	6 ft 3 in.
3-2x12	8 ft 2 in.	7 ft 4 in.	6 ft 9 in.

Add a floor above and the spans drop. With the roof, ceiling and one center-bearing floor at 30 psf, a 2-2x10 spans 5 ft 7 in., 5 ft 0 in. and 4 ft 7 in. for the same three building widths, and a 3-2x12 spans 7 ft 1 in., 6 ft 5 in. and 6 ft 0 in.

The calculator picks the header with the least lumber that spans your opening, and it only offers headers that fit inside the wall: two plies in a 2x4 wall (3 in. of lumber in a 3 1/2 in. wall), up to three in a 2x6 wall. If nothing in the table reaches, it tells you to use an engineered beam such as an LVL, sized by its maker or an engineer. The header cut length is the rough opening plus 1 1/2 in. for each jack stud at each end.

Building width is measured across the ridge. For widths between the columns, the table allows interpolation; the calculator asks you to take the next width up, which is the safe side.

Worked examples

A 24 ft bearing wall, 8 ft high, 2x4 at 16 in., two corners, a 36 in. door and a 36 in. window, roof and ceiling only. Layout: 288 ÷ 16 = 18, plus 1 = 19 studs. Corners: 2 × 2 = 4. Openings: the header table gives a 2-2x6 (4 ft 2 in. at 30 psf, 28 ft wide) with one jack each end, so each opening adds 2 kings and 2 jacks: 8 studs. Total 31 studs cut to 91 1/2 in. Plates: 72 ft, 6 pieces of 12 ft. Headers: 4 pieces of 2x6, each 39 in. long. Sheathing: 192 sq ft ÷ 32 = 6 sheets.

A 40 ft first-floor wall in 2x6 at 16 in., with three 6 ft openings, holding up the roof, ceiling and one center-bearing floor. Layout: 480 ÷ 16 + 1 = 31. Corners: 4. A 6 ft opening needs a 3-2x12 here (6 ft 5 in., two jacks each end), so each opening adds 2 kings and 4 jacks: 18. Total 53 studs. Plates: 120 ft, 8 pieces of 16 ft. Headers: 9 pieces of 2x12, each 6 ft 6 in.

The same wall framed the advanced way, holding up only the roof. At 24 in. with two-stud corners: 21 layout + 2 corner + 18 king and jack = 41 studs. The 6 ft openings take a 2-2x12 (6 ft 3 in.). That is 12 fewer studs than the first version of the wall.

Advanced framing: fewer studs, more insulation

Advanced framing, first published as optimum value engineering (OVE), uses less lumber and leaves more room for insulation. Building Science Corporation's BSI-030 describes the package: 2x6 studs at 24 in. on center, single top plates, two-stud corners, no jack studs or cripples, single headers, and no headers at all in walls that do not bear. It puts the saving at 5 to 10 percent less lumber and 30 percent fewer pieces.

Two-stud corners. The third stud of a conventional corner is there only to give the drywall something to nail to, and it blocks insulation from the corner. A clip or a 1x backer does the same job.
24 in. spacing. Fewer studs means less wood in the wall and fewer cold spots. Check that the sheathing and drywall you plan are rated for 24 in. spans.
Single top plate. Only with in-line framing and the plate joints tied, as above.

Switch the calculator between three-stud and two-stud corners and between 16 and 24 in. to see the difference on your own wall.

From a framing list to an estimate

The material list is the start of the price. Price each line from your lumber yard, then add labor. Framers often price walls by the linear foot or the square foot of wall, with extra for openings, corners and height. Press "Save as an estimate in Koira" to carry the studs, plates, headers, sheathing and wall footage over as lines, add your prices, and send it.

For the sheathing in more detail, with span ratings and nails, use the plywood and sheathing calculator. For lumber priced by the board foot, use the board foot calculator. To set your rate, see the labor rate calculator.

A take-off, not a designStud size and spacing, header sizes, bracing and connections follow the code adopted where you build and the plans. Spans here are for No. 2 southern pine from the NC table; other species have their own spans in IRC Table R602.7(1). The inspector has the last word.

Last checked October 8, 2026. More for your trade: how remodelers run on Koira.

FAQ

How do you calculate how many studs you need?

Wall length in inches ÷ stud spacing, rounded up, plus one for the end. Then add 2 studs per corner (three-stud corners), and 2 king studs plus the jack studs for each door and window. A 24 ft wall at 16 in. with two corners and two openings is 19 + 4 + 8 = 31 studs.

How many studs for a 12 foot wall?

At 16 in. on center, 144 ÷ 16 = 9, plus 1 = 10 layout studs. At 24 in., 7. Add corners and openings on top.

What size header do I need for a 6 foot opening?

It depends on the load. In the NC table for No. 2 southern pine at 30 psf, a wall holding up only the roof and ceiling of a 28 ft wide house needs a 2-2x12 (6 ft 3 in.). With a center-bearing floor above, a 3-2x12 (6 ft 5 in.). Your local code table and inspector govern.

How many plates does a wall need?

A bottom plate and a double top plate in conventional framing, so three times the wall length. A single top plate needs in-line framing and tied plate joints, and your code and inspector have to accept it.

How long should studs be for an 8 foot wall?

With a bottom plate and a double top plate, 96 − 4 1/2 = 91 1/2 in., since each plate is 1 1/2 in. thick. Yards also sell precut studs for standard wall heights.

Is 24 inch stud spacing allowed?

Often, yes. Advanced framing uses 2x6 studs at 24 in. on center. Whether it works on your wall depends on the stud size, the load, the wall height and what the sheathing and drywall are rated for, under the code your jurisdiction adopted.

More free tools

Trade mathPlywood and sheathing calculatorSheets, span rating, clips and nails for a roof, wall or floor.Trade mathBoard foot calculatorBoard feet, linear feet and cost for a lumber order.Trade mathDrywall calculatorDrywall sheets, joint compound, tape and screws for a room or an area.Trade mathConcrete block calculatorBlocks, mortar, grout and rebar for a CMU wall.