How many studs do I need for a wall?

Studs along the wall = floor(wall length in inches ÷ spacing) + 1. A 20 ft wall (240 in) at 16 in on center is 240 ÷ 16 = 15 spaces, so 16 studs, or 18 with 10% extra. Corners, intersections and openings add more, so use the calculator for the whole wall. The reference table lists the count for 8 to 40 ft walls at 16 and 24 in.

How many studs does a corner or a T-intersection add?

This calculator adds 2 studs for each corner and 2 for each T-intersection. A common 3-stud corner has two studs more than a plain end, and a T needs backing so the partition wall has something to nail to. Those are typical numbers, not a rule: your plans may call for a different corner or for drywall clips, so change the counts to match.

How do I frame a door or window opening?

Each opening has 2 king studs (full height, one on each side), 2 jack studs (shorter, carrying the header), a header across the top of the jacks, and short cripple studs above it, and below a window’s sill. This calculator counts 4 studs for the kings and jacks, a header the opening width + 3 in long, doubled, and cripples at the same spacing as the wall. The 36 in door and two 36 in windows in the example add 12 studs and 20 ft of header lumber. This is a simplified estimate: header sizes for a load-bearing wall come from your code’s span tables or an engineer.

What size header do I need?

It depends on the span, the load the wall carries and your local code, so this calculator does not pick it: choose the size you were given, and it counts the lumber. In the US the IRC has span tables for headers in load-bearing walls (Table R602.7(1) in recent editions), by lumber size, species, span and what sits above. A header in a non-bearing wall can be much lighter. If the wall carries a roof, a floor or another wall, have it checked by an engineer or building official.

What length of stud should I buy for an 8, 9 or 10 ft wall?

The common precut studs are 92 5/8 in for 8 ft walls, 104 5/8 in for 9 ft and 116 5/8 in for 10 ft. With a bottom plate and a double top plate (three 1.5 in boards) they make a wall 97 1/8, 109 1/8 or 121 1/8 in high, so a 4 × 8 ft drywall sheet hung across the wall fits. These are common trade lengths rather than a standard; some yards and regions stock others.

Should I space studs 16 or 24 inches on center?

16 in is the usual spacing and it suits most drywall and sheathing. 24 in saves lumber (11 studs along a 20 ft wall against 16 at 16 in) but is allowed only in some walls, often those with 2 × 6 studs or carrying a light load; check the code table for your wall height, load and lumber. Follow your plans.

How many plates do I need?

A bottom plate plus a double top plate is three runs of the wall length. A 24 ft wall needs 72 ft of plate, 79.2 ft with 10% extra, which is 5 boards of 16 ft. Longer boards leave fewer splices; pick the length with the least left over (the table of plate boards by wall length shows how the count changes). Top plate splices must be offset between the two layers.

How many nails or screws do I need?

The count depends on the fastening schedule in your code (for example, two 16d nails to the plate at each stud end), so it is not shown here: it would be a guess. Count it from your plans: studs × nails per end, plus the plates and headers. A framing nailer and a box of 16d nails is a common start.

Is this a structural design?

No. It is a material estimate for shopping. Wall layout, load paths, stud and header sizes, bracing, fire-blocking, anchor bolts and fasteners come from your local building code and your plans. A load-bearing wall, a wide opening or anything that carries a roof or a floor should be checked by an engineer or your building department before you buy or cut.

Wall Framing Calculator: How Many Studs Do I Need?

A 24 ft long, 8 ft high wall framed at 16 in on center, with 2 corners, 1 T-intersection, a door and two windows, needs about 37 studs (92 5/8 in precut) with 10% extra: 13 along the wall, 6 for the corners and the T, 12 king and jack studs at the openings and 2 to cut the cripples from. Add 5 plate boards of 16 ft (a bottom plate and a double top plate, 3 times the wall length), 20 ft of header lumber and about 270 board feet of lumber in all. Studs along a wall = floor(length in inches ÷ spacing) + 1. This is a material estimate, not a structural design: load-bearing walls and headers follow your local code and, where it asks, an engineer.

Figures based on the sources listed belowUpdated 2026-10-04How we calculate

Wall length

Wall height

Extra studs and plates

Standard: crowned and split studs, mis-cuts (10%)Many openings or corners (15%)Exact (0%)Custom

Stud spacingCheck your code and the wall’s load: 16 in is the usual spacing, and 24 in is allowed for some walls (often with 2 × 6 studs).

Stud and plate sizeOnly changes the board feet; the counts are the same.

Corners

Each adds 2 studs: a common 3-stud corner. Your plan may use a different corner (typical, not a rule).

Wall intersections (T)

Each adds 2 studs, for the partition wall to nail to (typical, not a rule).

Doors

Each adds 2 king and 2 jack studs, a header and cripples above it.

Door opening width (in)

The rough opening between the jacks, about 2 in wider than the door.

Windows

Each adds 2 king and 2 jack studs, a header, cripples above it and cripples below the sill.

Window opening width (in)

The rough opening between the jacks. All openings are taken to be 82 in high at the top, windows with a 36 in sill.

Header lumberTake the size from your code’s header tables or your plans; a load-bearing header must be sized for its load.

Plate board lengthPlates are a bottom plate and a double top plate, 3 times the wall length. Pick the length that wastes least.

Price per stud (optional)

Buy 37 studs

24 linear ft + 10% waste = 26.40 linear ft

Studs along the wall, at the spacing: 13 studs (each 92.63 in), 92 5/8 in precut
Extra studs for corners and T-intersections (typical): 6 studs
King and jack studs at openings: 12 studs, 6 king, 6 jack
Cripples above and below openings: 10 cripples, cut from 2 of the studs
Plate boards (bottom plate and double top plate, 16 ft boards): 5 boards (for 79.2 ft)
Header lumber (doubled 2 × 8, simplified): 20 ft, check header sizes against your code
Total lumber to buy (nominal size): 270 board feet

Low

$111.00

Expected

$166.50

High

$259.00

Includes 2.40 linear ft waste

How this number is calculated

24 linear ft + 10% waste = 26.40 linear ft ÷ 0.714 linear ft per stud = 37 studs

Shopping list

Framing nailer
Framing nails (16d)
Chalk line
Framing square
4 ft level
Stud finder

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Studs by wall length at 16 and 24 in on center

Studs along a plain wall = floor(length in inches ÷ spacing) + 1, worked by this calculator with no corners, openings or extra percentage. Add 2 for each corner and T, 4 for each opening, and about 10% for waste.
Wall length	Studs at 16 in on center	Studs at 24 in on center
8 ft	7	5
10 ft	8	6
12 ft	10	7
14 ft	11	8
16 ft	13	9
20 ft	16	11
24 ft	19	13
28 ft	22	15
32 ft	25	17
36 ft	28	19
40 ft	31	21

Plate boards by wall length and board length

A bottom plate and a double top plate is 3 times the wall length. Boards are rounded up, with no extra percentage, worked by this calculator.
Wall length	Plate length	8 ft boards	10 ft boards	12 ft boards	16 ft boards
8 ft	24 ft	3	3	2	2
10 ft	30 ft	4	3	3	2
12 ft	36 ft	5	4	3	3
14 ft	42 ft	6	5	4	3
16 ft	48 ft	6	5	4	3
20 ft	60 ft	8	6	5	4
24 ft	72 ft	9	8	6	5
28 ft	84 ft	11	9	7	6
32 ft	96 ft	12	10	8	6
36 ft	108 ft	14	11	9	7
40 ft	120 ft	15	12	10	8

Methodology & assumptions

This is an estimate of lumber, counted from simple rules you can check, not a structural design. Wall length, wall layout, load paths, header sizes, stud grade and size, spacing, bracing, fire-blocking and fastening are set by your local code (in the US usually the International Residential Code, chapter 6) and, for a load-bearing wall or a wide opening, by your plans or an engineer. Use the counts to shop, not to decide how to build. Studs along the wall: the layout studs sit at the chosen spacing starting from one end, so there are floor(wall length in inches ÷ spacing) + 1 of them, the last closing the end. A 24 ft wall is 288 in, and 288 ÷ 16 = 18 spaces, so 19 studs. Corners and T-intersections add studs: this calculator adds 2 for each, as a common 3-stud corner and a T with backing for the partition does. Those are typical, not a rule; your framing plan (a ladder or California-style corner, drywall clips) may use more or fewer. Openings: each door or window adds 2 king studs (full length, either side) and 2 jack studs (they carry the header, cut shorter but bought as a stud each). The layout studs that fall inside the opening, floor(opening width ÷ spacing), are not built, so they come off the count. Above the header, and below a window, short cripple studs fill the space at the same spacing: at least one, otherwise floor(opening width ÷ spacing). Cripples are counted in inches and turned into whole studs once for the whole wall. To do this the calculator takes one fixed shape for every opening: the top of the rough opening 82 in above the floor, a window sill 36 in above the floor, 1.5 in plates and sill, and a header whose depth is the lumber you pick. The header is two members the width of the opening plus 3 in, for the two 1.5 in jack studs it sits on. The window sill itself and the notch in the bottom plate at a door are not counted; the extra percentage covers them. Plates: one bottom plate and a double top plate is three runs, 3 times the wall length, and the plate boards come from that length plus the extra percentage, divided by the board length you pick and rounded up. Plates continue across a window, and a door’s bottom plate is cut out after the wall is framed; a plate board that is shorter than the wall is spliced, and the top plates’ splices are offset, which the waste allowance pays for. Stud length follows the wall height. The common precut lengths are 92 5/8 in for an 8 ft wall, 104 5/8 in for 9 ft and 116 5/8 in for 10 ft; with a bottom plate and a double top plate (4.5 in) these make a wall 97 1/8, 109 1/8 or 121 1/8 in high, which suits 4 × 8, 4 × 9 and 4 × 10 ft drywall sheets run across the wall. Taller walls take 12 ft studs (then 14 and 16 ft) cut to fit. Lumber lengths vary by region, so check what your yard stocks. The headline adds the extra percentage (10% is typical for crowned, split or mis-cut studs) to all the studs and rounds up once. The board feet are the nominal size, thickness × width × length ÷ 144, from the board foot calculator’s helper: the studs and plate boards you buy plus the header lumber, which carries no extra percentage. A 2 × 4 is counted as 2 × 4 although it measures 1.5 × 3.5 in. Nails are not shown: the count depends on the fastening schedule in your code, not on the geometry. The metric toggle shows wall lengths in m and opening widths in cm.

International Residential Code (IRC), Chapter 6 Wall Construction, Section R602 Wood wall framing: stud size, height and spacing (Table R602.3(5)), top plates, and the header spans in Table R602.7(1) (section and table numbers differ between editions)
American Softwood Lumber Standard (PS 20): nominal and actual sizes of dimension lumber, a 2 × 4 being 1.5 × 3.5 in and a 2 × 6 being 1.5 × 5.5 in
Precut stud lengths (92 5/8, 104 5/8 and 116 5/8 in) are common trade practice at US lumber yards, not a standard: they suit 8, 9 and 10 ft walls with one bottom plate and a double top plate; check what your supplier stocks
The counts for corners, T-intersections, cripples and the 82 in opening height are this calculator’s simplified rules of thumb (estimates), described under Methodology

How to estimate studs for a wall

Measure the wall. Measure the length of the wall and its height, and choose the stud length that matches the height: 92 5/8 in for 8 ft, 104 5/8 in for 9 ft, 116 5/8 in for 10 ft.
Count the studs at the spacing. Divide the length in inches by the spacing (16 or 24), round down, and add 1 for the end stud.
Add the corners and intersections. Add 2 studs for each corner and each T-intersection, or the number your framing plan shows.
Frame the openings. Each door or window takes 2 king and 2 jack studs, a doubled header the opening width plus 3 in long, and cripples above it (and below a window). Take off the layout studs inside the opening.
Add the plates and the waste. Plates are 3 times the wall length (a bottom plate and a double top plate), divided by the board length. Add about 10% to the studs and plates and round up.

Worked examples

Project	Result
24 ft wall, 8 ft high, 16 in on center, 2 corners, 1 T, a 36 in door and two 36 in windows	37 studs (92 5/8 in), 5 plate boards of 16 ft, 20 ft of header lumber, about 270 board feet
20 ft plain wall, 8 ft high, 16 in on center, no corners or openings	18 studs (92 5/8 in), 5 plate boards of 16 ft, about 146 board feet
The same 20 ft wall at 24 in on center	13 studs (92 5/8 in), 5 plate boards of 16 ft, about 121 board feet
30 ft wall, 9 ft high, 24 in on center, 2 corners, 1 T, 2 doors and 3 windows (36 in)	43 studs (104 5/8 in), 7 plate boards of 16 ft, 33 ft of header lumber, about 368 board feet
16 ft wall, 10 ft high, 16 in on center, 1 corner and a door, with 12 ft plate boards	20 studs (116 5/8 in), 5 plate boards of 12 ft, 7 ft of header lumber, about 179 board feet
The first wall with no openings (an unbroken 24 ft wall with its corners and T)	28 studs (92 5/8 in), 5 plate boards of 16 ft, 0 ft of header lumber, about 198 board feet

Frequently asked questions

How many studs do I need for a wall?: Studs along the wall = floor(wall length in inches ÷ spacing) + 1. A 20 ft wall (240 in) at 16 in on center is 240 ÷ 16 = 15 spaces, so 16 studs, or 18 with 10% extra. Corners, intersections and openings add more, so use the calculator for the whole wall. The reference table lists the count for 8 to 40 ft walls at 16 and 24 in.
How many studs does a corner or a T-intersection add?: This calculator adds 2 studs for each corner and 2 for each T-intersection. A common 3-stud corner has two studs more than a plain end, and a T needs backing so the partition wall has something to nail to. Those are typical numbers, not a rule: your plans may call for a different corner or for drywall clips, so change the counts to match.
How do I frame a door or window opening?: Each opening has 2 king studs (full height, one on each side), 2 jack studs (shorter, carrying the header), a header across the top of the jacks, and short cripple studs above it, and below a window’s sill. This calculator counts 4 studs for the kings and jacks, a header the opening width + 3 in long, doubled, and cripples at the same spacing as the wall. The 36 in door and two 36 in windows in the example add 12 studs and 20 ft of header lumber. This is a simplified estimate: header sizes for a load-bearing wall come from your code’s span tables or an engineer.
What size header do I need?: It depends on the span, the load the wall carries and your local code, so this calculator does not pick it: choose the size you were given, and it counts the lumber. In the US the IRC has span tables for headers in load-bearing walls (Table R602.7(1) in recent editions), by lumber size, species, span and what sits above. A header in a non-bearing wall can be much lighter. If the wall carries a roof, a floor or another wall, have it checked by an engineer or building official.
What length of stud should I buy for an 8, 9 or 10 ft wall?: The common precut studs are 92 5/8 in for 8 ft walls, 104 5/8 in for 9 ft and 116 5/8 in for 10 ft. With a bottom plate and a double top plate (three 1.5 in boards) they make a wall 97 1/8, 109 1/8 or 121 1/8 in high, so a 4 × 8 ft drywall sheet hung across the wall fits. These are common trade lengths rather than a standard; some yards and regions stock others.
Should I space studs 16 or 24 inches on center?: 16 in is the usual spacing and it suits most drywall and sheathing. 24 in saves lumber (11 studs along a 20 ft wall against 16 at 16 in) but is allowed only in some walls, often those with 2 × 6 studs or carrying a light load; check the code table for your wall height, load and lumber. Follow your plans.
How many plates do I need?: A bottom plate plus a double top plate is three runs of the wall length. A 24 ft wall needs 72 ft of plate, 79.2 ft with 10% extra, which is 5 boards of 16 ft. Longer boards leave fewer splices; pick the length with the least left over (the table of plate boards by wall length shows how the count changes). Top plate splices must be offset between the two layers.
How many nails or screws do I need?: The count depends on the fastening schedule in your code (for example, two 16d nails to the plate at each stud end), so it is not shown here: it would be a guess. Count it from your plans: studs × nails per end, plus the plates and headers. A framing nailer and a box of 16d nails is a common start.
Is this a structural design?: No. It is a material estimate for shopping. Wall layout, load paths, stud and header sizes, bracing, fire-blocking, anchor bolts and fasteners come from your local building code and your plans. A load-bearing wall, a wide opening or anything that carries a roof or a floor should be checked by an engineer or your building department before you buy or cut.

Handy tools

Board Foot Calculator: Price the lumber by the board foot, or work out the board feet for a different cut list.
Feet and Inches Calculator: Add up wall lengths and opening widths measured in feet, inches and fractions.