Free calculator
Drywall Calculator
Enter a room to get board area, sheets by size, joint compound, tape and screws. Add your own prices to get the installed cost, then add the room to an estimate and do the next one.
- Sheets, mud, tape, screws
- Your prices, saved
- Builds an estimate
- No email required
Room
Board and finish
Your prices
Optional. Saved in this browser, so you only type them once.
Your estimate
Saved in this browser. Add rooms or runs from any of our calculators.
Nothing here yet. Run the numbers above and press “Add to estimate”.
Ready to send this as a proposal?
BuildWorkPro builds bids from line items like these, with your margin and overhead, and turns them into a PDF proposal. $79/mo flat, free for 14 days.
Start free trialHow it’s calculated
Board area. Walls are the room’s perimeter times the wall height: 2 × (length + width) × height. Openings you choose to deduct come off at 20 sq ft per door and 15 sq ft per window. The ceiling, when included, is length × width.
Sheets. Walls and ceiling are counted separately: area × (1 + waste) ÷ sheet area, rounded up. A 4 × 8 sheet is 32 sq ft, a 4 × 10 is 40 and a 4 × 12 is 48.
Joint compound and tape. USG product data puts ready-mixed compound at about 9.4 gallons and paper tape at about 370 feet per 1,000 sq ft of board. Pails are 4.5 gallons and rolls are 500 feet, rounded up.
Screws. Each sheet is hung across framing 16" on center, with one row of screws per framing member at the ASTM C840 maximum spacing: 16" on walls and 12" on ceilings. Your framing, the board and the assembly can call for more.
Price. Material is quantity × your unit price for each item you priced. Labor is board area × your hang-and-finish rate. Nothing is priced with numbers you did not enter.
Pricing a whole job? The drywall estimate template has a takeoff sheet and a customer-facing estimate grouped into hang, finish and texture.
Board prices. The drywall price trend shows how gypsum board prices have moved over the last year, so you know whether last quarter’s per-sheet price still holds.
Keep going
More free tools and price data: Labor Burden Calculator · Markup vs Margin Calculator · Drywall Prices
Frequently asked questions
How many sheets of drywall do I need for a 12 × 12 room?
With 8-foot walls, the ceiling included, no openings deducted and 10% waste, a 12 × 12 room needs 19 sheets of 4 × 8 board: 14 for the 384 sq ft of walls and 5 for the 144 sq ft ceiling. In 4 × 12 sheets it is 9 for the walls and 4 for the ceiling. The calculator rounds walls and ceiling separately, because they are usually hung and often bought as different board.
How much joint compound do I need per sheet of drywall?
USG puts ready-mixed compound at about 9.4 gallons per 1,000 sq ft of board, which is roughly 0.3 gallons per 4 × 8 sheet. A 4.5-gallon pail finishes about 480 sq ft, or around 15 sheets of 4 × 8. Level 5 work adds a skim coat over the whole surface, so plan on more.
How many screws go in a sheet of drywall?
Hung across framing 16 inches on center with screws at the ASTM C840 maximum spacing (16 inches on walls, 12 inches on ceilings), a 4 × 8 sheet takes about 28 screws on a wall and 35 on a ceiling. A 4 × 12 sheet takes about 40 on a wall and 50 on a ceiling. Tighter spacing, adhesive or fire-rated assemblies change the count.
Should I deduct doors and windows?
Many hangers deduct only large openings, because the board cut out of a standard door or window is mostly scrap and deducting it undercounts sheets. So the example deducts nothing. Enter a count of doors or windows to deduct 20 sq ft per door and 15 sq ft per window, for rooms where the openings are large or numerous.
What do drywall finish levels 3, 4 and 5 mean?
They are the Gypsum Association’s GA-214 levels of finish. Level 3 is for walls getting a medium or heavy texture. Level 4 is the usual finish for flat paint and light texture. Level 5 adds a skim coat over the whole surface, for gloss paint or walls under raking light. The level you pick is written on the labor line of your estimate.
Are my measurements and prices sent to BuildWorkPro?
The calculator sends nothing: the math runs in your browser, and your prices and your estimate are saved in this browser’s local storage, never on our servers. The room size is kept in the page address so you can bookmark or share a result; like any page address, it is recorded by our site analytics if you accept analytics cookies.