Drywall Calculator
Estimate drywall sheets for walls and optional ceiling.
Use decimals when needed. This estimate updates live and is safe to tweak before you buy materials.
Drywall Buying Guide
This guide helps you turn your drywall calculator result into a cleaner purchase plan. Use it when you want fewer return trips, better waste assumptions, and a more realistic cart.
Step 1: Measure ceiling and walls separately
Always calculate ceiling drywall first, as it's installed before the walls. For walls, measure total linear feet and multiply by ceiling height.
Step 2: Choose the right sheet size
Standard sheets are 4x8 feet, but using 4x12 sheets means fewer joints to tape and sand. If you can maneuver larger sheets into the room, use them.
Step 3: Ignore doors and windows
When buying drywall, do not subtract for doors and windows unless they are massive. You will run the drywall right over the openings and cut them out.
Recommended for this job
Commonly paired tools and accessories
These are the practical extras people often forget until the last minute, especially when turning a rough estimate into a real purchase list.
Drywall liftWhy this helps: Common add-on that reduces last-minute store runs once the estimate is final.
Joint tape rollWhy this helps: Common add-on that reduces last-minute store runs once the estimate is final.
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Drywall cost planning rule of thumb
You need the gypsum panels, drywall screws, paper tape, corner bead, and plenty of joint compound (mud) to finish the job.
Understanding the Math
Formula: The basic formula for Drywall Calculator typically involves calculating the total area or volume (Length × Width × Depth) and dividing by the coverage of a single unit or package, then adding a waste factor (usually 10%).
Example: For example, if you have a 10x10 area and your material covers 10 square feet per unit, you need 10 units. With a 10% waste factor, you should purchase 11 units to ensure you don't run short.
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Drywall Calculator FAQ
Do I need moisture-resistant board?
Use moisture-resistant board in bathrooms, laundry rooms, and damp spaces.
What size sheet is best?
4x8 is common for DIY handling. Longer sheets reduce seams in larger rooms.
What thickness of drywall should I use?
Use 1/2-inch for most walls, 5/8-inch for ceilings (to prevent sagging) and fire-rated walls, and 1/4-inch or 3/8-inch for curved surfaces.
How many screws per sheet?
A standard 4x8 sheet typically requires around 32 screws when fastening to studs spaced 16 inches on center.