Primary material
19 sheets
Drywall sheets
Use the sheet count as a buying starting point, then confirm the sheet size, thickness (1/2 in walls, 5/8 in ceilings), and moisture or fire rating.
Drywall calculator
Drywall calculator for sheets, mud, tape, and screws.
Enter the room size to estimate drywall sheets plus the joint compound, tape, screws, and studs to finish it. A 12 x 12 room with 8 ft walls and a ceiling needs about 19 sheets.
12 x 12 x 8 ft + ceiling
19 sheets
528 sq ft
Per 4 x 8 sheet
~0.5 gal
mud + 40 ft tape
Screws
~32 / sheet
field and edges
Quick reference
Drywall sheets for common room sizes
Walls plus ceiling at 8 ft high with the default 10% waste, before subtracting doors and windows.
| Room size | Board area | 4x8 sheets | 4x12 sheets | Joint compound |
|---|---|---|---|---|
| 10 x 10 ft | 420 sq ft | 15 | 10 | 7.5 gal |
| 12 x 12 ft | 528 sq ft | 19 | 13 | 9.5 gal |
| 12 x 16 ft | 640 sq ft | 22 | 15 | 11 gal |
| 16 x 20 ft | 896 sq ft | 31 | 21 | 15.5 gal |
| 20 x 20 ft | 1,040 sq ft | 36 | 24 | 18 gal |
Measure each wall and the ceiling. Most estimators do not subtract ordinary doors and windows.
Quick drywall answers
Sheets for common rooms
10 x 10 room
8 ft walls + ceiling
15 sheets
4 x 8 panels with 10% waste
12 x 12 room
8 ft walls + ceiling
19 sheets
4 x 8 panels with 10% waste
12 x 16 room
9 ft walls + ceiling
24 sheets
4 x 8 panels with 10% waste
Thickness matters
Walls usually use 1/2 in drywall; ceilings often use 5/8 in to resist sag, and 5/8 in Type X where fire rating is required. Wet areas use moisture- or mold-resistant board.
Shopping list
Sheets, mud, tape, and tools
The sheet count updates from the calculator. Confirm sheet size, thickness, and finish level before ordering.
Finishing
Joint compound and tape
Plan all-purpose mud by the box and joint tape by the roll. Coverage varies with finish level — the estimate assumes a standard 3-coat job.
Fasteners and trim
Screws and corner bead
Drywall screws (1-1/4 in for 1/2 in board), plus corner bead for outside corners and a few extras for repairs.
Install tools
Knives, sander, and lift
Taping needs 6 and 12 in knives, a mud pan, a pole sander, a utility knife and T-square, and a panel lift for ceilings.
Formula shown
How the drywall estimate works
1. Area to cover
walls = 2 x (length + width) x height; + ceiling = length x width
2. Sheets
sheets = ceil(area x (1 + waste) / sheet coverage)
3. Finishing per sheet
mud ~0.5 gal, tape ~40 ft, screws ~32 per 4 x 8 sheet
What this leaves out
Corner bead, furring, insulation, vapor barrier, soundproofing, and specialty board (moisture, mold, or fire-rated) are separate. The stud count assumes simple new 16 in OC framing without openings or blocking.
Sources
- Inch Calculator drywall estimating — sheets, mud, tape, and screw coverage per sheet
- USG drywall installation — panel sizes, fastener spacing, and finishing guidance
- Steeler drywall material estimator — framing, fastener, and finishing material rules
Sources checked
Checked against
Sheet, compound, and insulation coverage checked against manufacturer specs and DOE R-value guidance.
How we check our numbersLast updated: June 26, 2026
Estimate only.
This calculator is not a quote. Verify product yield, price, delivery minimums, and local conditions with your supplier or contractor before buying materials.
Related
Finish the room
Guide: How many sheets of drywall do I need? Wall and ceiling area, 4x8 vs 4x12, mud, tape, and screws. Insulation calculator Insulate the walls and ceiling before the drywall goes up. Paint calculator Once the drywall is finished, estimate paint and primer for the room. Flooring calculators Finish the room — boxes, tile, and underlayment.
FAQ
Drywall calculator questions
Sheets, mud and tape, sheet sizes, openings, and screws for a room.
How many sheets of drywall do I need for a 12x12 room? + -
A 12 x 12 room with 8 ft walls and a ceiling is about 528 sq ft. With 10% waste and 4 x 8 sheets (32 sq ft each), that is about 19 sheets. Larger 4 x 12 sheets cut the count but are heavier to handle.
How much joint compound and tape do I need? + -
A common rule for a standard 3-coat finish is about half a gallon of all-purpose mud and 40 linear feet of tape per 4 x 8 sheet. Coverage changes with finish level and how much sanding you do.
Should I use 4x8 or 4x12 drywall? + -
4 x 8 sheets are easier to carry and fit through doorways; 4 x 12 sheets cover more and leave fewer joints to tape, which speeds finishing on long walls and ceilings — but they are heavy and awkward for one person.
Do I subtract doors and windows? + -
Usually not for a planning estimate. Most installers sheet right over openings and cut them out, so the offcuts cover some waste. For big openings or a tight budget, you can subtract their square footage.
How many screws per sheet of drywall? + -
About 32 screws per 4 x 8 sheet — roughly one every 12 inches in the field and every 8 inches along the edges, driven into the studs and ceiling joists.