How to use it
Enter the length to lay out and the on-center spacing. You get the number of members with one at each end, the number of spaces, the size of the last bay if you hold the spacing, and the equal spacing that divides the length exactly.
Worked example
A 12' 6" wall at 16" on center takes 11 studs. Holding 16" leaves a last bay of 6". If you would rather space them evenly, 10 equal spaces of 15" fill the length exactly.
Things to know
- The count includes a member at both ends. It does not add extra studs for corners, openings, or the doubled studs at wall intersections.
- Use the fixed spacing for studs, joists and rafters, so that 4' sheets land on a framing member.
- Use the equal spacing for balusters, pickets, shelves, slats and anything else that should look even.
- Common spacings are 12", 16", 19.2" and 24" on center.
Typing measurements
Every box takes feet, inches and fractions the way you would write them: 9' 1 1/8", 7 1/2", 2.5' or 300mm. Put a space between whole inches and a fraction. A box also takes a whole calculation, so 14' 6" / 2 works anywhere.
Questions
How many studs do I need for a wall?
Divide the wall length by the spacing, round up, and add one for the end. A 12' 6" wall at 16" on center needs 11 studs. Add more for corners, openings and intersecting walls.
What does on center mean?
The distance from the centre of one framing member to the centre of the next. At 16" on center, the gap between 1 1/2" thick studs is 14 1/2".
How do I space things evenly across a length?
Divide the length by the number of spaces. The calculator finds the number of spaces that keeps you at or under your target spacing and gives the exact equal spacing.
How precise is the answer?
The math is done at full precision and only the displayed fraction is rounded, to the nearest 1/16 inch by default. You can change that from 1/2 down to 1/64. When rounding changes the value, the answer is marked with ≈.
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