About the Wall Stud Calculator
Framing a wall begins with the studs, the vertical pieces that hold up the covering. This calculator takes the length of the wall and the stud spacing and gives the number of regular studs, then adds the extra studs needed at corners and around doors and windows. It includes the common spacings of 16 and 24 inches and 400 and 600 millimetres. Type the wall length, the spacing, the number of corners and the number of openings and the wall studs appears at once, with a few related figures underneath, and you can copy the result with one tap. The sums run in your browser, so nothing you enter is uploaded.
Updated October 2026
How to use the Wall Stud Calculator
- 1Enter the wall length, the spacing, the number of corners and the number of openings.
- 2Pick the units or options from the menus if the wall studs tool offers them.
- 3Read the wall studs in the large result box.
- 4Look at the extra rows for related figures.
- 5Press Copy result to keep the answer.
When you need the wall studs
Builders and DIY carpenters use it to make a materials list, and to price a partition wall or a shed. Choosing 24 inch spacing uses fewer studs but needs thicker boards or stiffer covering.
The common rule in the US is 16 inches on centre for walls that carry loads, 24 inches for non-loadbearing walls and some advanced framing. In metric countries 400 or 600 mm is common to suit board widths of 1,200 mm.
How the wall studs is worked out
Regular studs = wall length ÷ spacing + 1. Add about 2 extra studs for each corner and 4 for each door or window opening. A 20 foot wall with studs at 16 inches (1.333 feet) needs 16 regular studs. With two corners and one window, add 8 extra for a total of 24. With 10 percent spare, that is 27.
Every answer on this page comes from that one rule, so you can check any result by hand with a calculator. The figures shown underneath, such as other units, are conversions of the same answer.
- Four standard spacings
- Corners and openings
- 10% spare shown
Mistakes to avoid with wall studs
Use feet for the 16 and 24 inch options and metres for 400 and 600 mm so the units match. The tool counts the studs only: you also need top and bottom plates, noggins (blocking) and headers over openings. Follow your local building code.
On phone and computer
On a phone, type into the boxes one after another and read the wall studs underneath; Copy result puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the wall studs move. The wall stud calculator works the same on both. Studs are just one part of a wall. Plan the boards with the Drywall Calculator, the paint with the Paint Calculator, and the roof above with the Roofing Calculator.
Features
- Match units to spacing
- Plates and headers are extra
- Follow local codes
- Clear messages when the wall studs inputs make no sense
- Copy the result with one tap
- Private: nothing is uploaded
Frequently asked questions
How do I calculate wall studs?
Regular studs = wall length ÷ spacing + 1. Add about 2 extra studs for each corner and 4 for each door or window opening. A 20 foot wall with studs at 16 inches (1.333 feet) needs 16 regular studs. With two corners and one window, add 8 extra for a total of 24. With 10 percent spare, that is 27.
What is the formula for wall studs?
Regular studs = wall length ÷ spacing + 1. Add about 2 extra studs for each corner and 4 for each door or window opening. The wall stud calculator applies it exactly and rounds only the displayed answer to six significant figures.
What does on centre mean?
The distance from the centre of one stud to the centre of the next.
Why add studs at corners?
Corners need extra studs to nail the boards on both walls and to keep the corner solid.
How many studs per opening?
At least four: two king studs and two jack studs; large openings need more and a header.
Is this wall stud calculator free and private?
Yes. It is free, needs no account and runs in your browser, so the numbers you type are not uploaded or stored.