Stud Calculator
Studs = wall length in inches ÷ 16, rounded up, plus one, then one each side of an opening and one per corner: a 14 ft wall with a window and two corners takes 16 studs, or 18 with 10% extra.
Example: replace these measurements
Your framing list
18 2x4 studs+ 1 more item on the list
18 2x4 studs
Your shopping list
- 18 2x4 studs
- 3 plate boards, 16 ft
Quantities and package details
- Bedroom wall
- 12 on 16-in centers + 2 at openings + 2 at corners = 16 studs
- Studs before extra
- 16
- Studs to buy
- 18
- Stud length
- 92 5/8 in, the precut stud for an 8 ft wall
- Plate lumber
- 42 ft (bottom plate and double top plate)
- Plate boards, 16 ft
- 3
The calculation
- Bedroom wall: 168 in ÷ 16 = 10.5, rounded up, + 1 = 12 studs; + 2 × 1 opening + 2 corners = 16
- 16 × (1 + 10/100) = 17.6, rounded up to 18 studs
- Plates: 3 × 14 ft = 42 ft; each wall in 16-ft boards, 3 rows
Not measured yet? Common sizes
A rough starting point, worked out with this calculator. 8 ft walls, studs on 16-inch centers, no openings or corners, 10% extra; 16 ft plate boards. Use a row to load its size into the calculator, then change it to your measurements.
| Wall | Studs on 16 in centers | Studs to buy | Plate boards | Load |
|---|---|---|---|---|
| 8 ft wall | 7 | 8 | 3 | |
| 10 ft wall | 9 | 10 | 3 | |
| 12 ft wall | 10 | 11 | 3 | |
| 14 ft wall | 12 | 14 | 3 | |
| 16 ft wall | 13 | 15 | 3 | |
| 20 ft wall | 16 | 18 | 6 |
Common questions
How many studs do I need for a wall?
For studs on 16-inch centers, divide the wall length in inches by 16, round up and add one. A 12 ft wall is 144 ÷ 16 = 9, plus one: 10 studs. Add one on each side of a door or window and one at each corner, then about 10% for crooked boards.
How long are studs for an 8 ft wall?
92 5/8 inches. Sold as precut studs, they make a wall of 97 1/8 inches with a bottom plate and a double top plate, so 8 ft drywall reaches the ceiling with room for the ceiling board.
16 or 24 inches on center?
16 inches is the usual spacing for walls; 24 inches uses fewer studs and is common with 2x6 exterior walls. Your plans and the local code decide which a wall may use.
How many plates does a wall need?
Three rows the full length of the wall: one bottom plate and a double top plate. A 14 ft wall takes 42 ft of plate lumber, or three 16 ft boards.
How to plan the quantity
Studs on 16-inch centers: wall length in inches ÷ 16, rounded up, plus one for the end. A 14 ft wall is 168 ÷ 16 = 10.5, so 11 spaces and 12 studs.
Add one stud on each side of every door or window for the king and jack studs, and one at each corner or where another wall meets this one. Then add about 10% for crooked or split boards.
Plates run the full length three times: one bottom plate and a double top plate. For an 8 ft wall, buy precut studs of 92 5/8 inches: with the three plates the wall comes to 97 1/8 inches, ready for 8 ft drywall on the ceiling. For 9 and 10 ft walls the precuts are 104 5/8 and 116 5/8 inches.
Before you order
- Stud size, spacing and the header over each opening come from your plans and the local code: this counts boards, it does not size them.
- Headers, cripple studs, blocking and fire blocking add lumber this does not count. Ask the lumber yard to check the list against the plan.
Before ordering, read the guide: How many sheets of drywall do I need? Sheets, tape, mud and screws. Or choose another calculator.