Stud Calculator
Wall studs at 16 or 24 inch centres, openings, plates and waste.
About this tool
Enter the wall length, stud spacing, number of corners or wall ends and number of door and window openings. The tool counts field studs, the extra studs for corners and openings, the plate material and how many to buy with waste.
Counting studs
Framed walls have vertical studs at regular centres between a bottom plate and a top plate, doubled in typical North American framing. Spacing is usually 16 in (400 mm) on centre for load-bearing walls and often 24 in (600 mm) for partitions, matching the widths of plasterboard and sheathing sheets. The basic count is wall length รท spacing, rounded down, plus one for the end stud, so a 12 ft wall at 16 in centres needs 10 field studs. Every door or window adds roughly four more: a full-height king stud and a shorter jack (trimmer) stud on each side, with cripples and a header above or below. Corners and junctions with other walls need about two extra each to give a fixing for the drywall. Plates add three wall-lengths of timber for a single bottom and double top plate. Add 10โ15% waste for crooked or split lengths. Honest limits: framing practice varies by country, code and design. Headers, blocking, noggins, fire stops and engineered openings add material, and load-bearing walls must follow local building codes. Not building advice. The drywall calculator and the board foot calculator are related.
Frequently asked questions
How many studs do I need for a 12 foot wall?
10 at 16 in on centre (144 รท 16 + 1), plus extras for corners and openings.
What does 16 inches on center mean?
The centre of each stud is 16 inches from the centre of the next.
How many extra studs does a window need?
Usually four: a king and a jack stud on each side, plus cripples above and below.
Should I use 16 or 24 inch spacing?
16 in is standard for load-bearing walls; 24 in is common for non-load-bearing partitions where codes allow.
Is my data sent anywhere?
No. Everything is calculated in your browser, and nothing is stored or sent.