Estimate, not a quote.
Everything is worked out in your browser. Your answers are not sent or saved.
The room
The prices behind the estimate
Every number has a source and a date. Type your own price on any row to replace it. The estimate, the print sheet and the bid check all follow.
| Item | Low | Typical | High | Source | Your price |
|---|---|---|---|---|---|
| Drywall sheet, price per sheet (the size you chose)per sheet | – | – | – | Typed by useras of October 14, 2026Type your price | |
| Joint compound, price per 4.5 gallon paileach | – | – | – | Typed by useras of October 14, 2026Type your price | |
| Joint tape, price per 250 foot rolleach | – | – | – | Typed by useras of October 14, 2026Type your price |
Compare bids
Enter two to four bids and the square feet of drywall each one covers. Tick what each bid says it includes. A low price per square foot can leave things out.
Enter two bids to compare them.
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How to estimate drywall in five steps
- Describe the room. Type the length, width and wall height of the room. For a ceiling-only job or a walls-only job, pick that option and the calculator leaves the other surface out.
- Choose the ceiling and the sheet size. Say whether the ceiling is included, then pick 4 x 8, 4 x 10 or 4 x 12 foot sheets. Longer sheets mean fewer seams, but they are harder to carry through a house.
- Set the waste. The waste box starts at 10 percent on sheets. Raise it for a room with many corners and cut-outs, or lower it for a plain box. It changes the sheet count only.
- Read the list. You see the area, the number of sheets rounded up, joint compound in gallons and in 4.5 gallon pails, paper tape in feet and in 250 foot rolls, and screws.
- Add your prices and print. Where you know a price, type it to get a cost range. We never show a price we did not source. Compare bids per square foot, then print the bilingual sheet for your supplier.
What this calculator does, and what it does not
This page turns a room's measurements into a shopping list for drywall: sheets, joint compound, paper tape and screws. It adds up the wall area and, if you ask for it, the ceiling area, then works out each material from that one number.
It is an estimate, not a takeoff from plans. It cannot see a bulging wall, an odd angle, a stairwell or a vaulted ceiling. It also does not give prices of its own. If you type prices, the page uses them and marks them as yours.
How the area is worked out
The walls of a rectangular room are two walls as long as the room and two walls as wide as the room, all as tall as the ceiling. So the wall area is twice the length plus the width, times the wall height. The ceiling is the length times the width.
Take a room 12 feet long, 14 feet wide and 8 feet tall. The walls come to 2 x (12 + 14) x 8 = 416 square feet. The ceiling is 12 x 14 = 168 square feet. Walls plus ceiling is 584 square feet. With the ceiling left out, the same room is 416 square feet.
Why doors and windows are not subtracted
The calculator does not take the area of doors and windows away from the total. That is on purpose. Sheets are cut around an opening, and the pieces that come out of the middle are often too small to use anywhere else. Seams also have to land on framing, so a sheet cannot always be shifted to use up an offcut.
Leaving the openings in works like a built-in cushion. If your room has a large window wall or a wide archway, you can lower the waste box a little. If you are unsure, keep the default and ask your supplier how they count.
Sheets: size, waste and rounding up
The sheet count is the area plus the waste, divided by the area of one sheet, rounded up. A 4 x 8 sheet covers 32 square feet, a 4 x 10 covers 40 and a 4 x 12 covers 48.
Worked example. The 584 square foot room with 4 x 8 sheets and 10 percent waste: 584 x 1.10 = 642.4 square feet, divided by 32 is 20.075. You cannot buy 0.075 of a sheet, so the answer is 21 sheets.
A second example, with walls only. A room 10 x 10 feet with 8 foot walls has 2 x (10 + 10) x 8 = 320 square feet. With 10 percent waste that is 352 square feet, and 352 divided by 32 is a whole 11. The page shows 11 sheets, with nothing to round.
Wall and ceiling area are added into one total, so the sheet count is one number for the whole job.
Choosing a sheet size
Longer sheets mean fewer seams, and fewer seams mean less joint compound and tape to finish. A 12 foot sheet can run the full length of a long wall in one piece. The trade-off is weight and handling. A long sheet is heavy, flexes when you carry it, and is hard to turn through a hallway or up a stairwell.
The sheet size changes the sheet count, not the area. Try the three sizes and compare. Compound, tape and screws are worked from the area, so they stay close to the same whichever size you pick.
Joint compound, tape and screws
Joint compound and tape are estimated per 1,000 square feet of drywall, which is how makers publish them. The calculator uses about 9 gallons of compound per 1,000 square feet, a figure from a maker's published rate, and about 370 feet of paper tape per 1,000 square feet.
Back to the 584 square foot room. Compound: 584 / 1,000 x 9 = 5.256 gallons. A pail holds 4.5 gallons, so that is 2 pails. Tape: 584 / 1,000 x 370 = 216.08 feet, which fits in 1 roll of 250 feet. Screws: 21 sheets x 32 square feet is 672 square feet of board, so about 672 screws.
The screw count is a common rule of thumb, about one screw for every square foot of board. It is a typed assumption, not a maker's number. Check the package and the spacing your installer plans to use, and ask your supplier.
Finishing takes several coats
Hanging the sheets is the first part of the job. Finishing is a series of steps: tape and a first coat of compound over the seams and screw heads, one or more further coats that are wider each time, sanding, and then primer. Each coat has to dry before the next.
The per-1,000 square feet figure is a planning number for a normal finish. A skim coat over the whole surface, a textured finish or a rough first pass will use more. Check the label for coverage and ask your supplier how many coats the product is meant for.
Ordering and leftovers
Sheets are sold whole, so you order a whole number. Compound is sold in pails and tape in rolls, so those round up too. The page shows the amount you need before rounding and the amount you would buy, and the difference is your leftover.
Leftover sheets are useful for patches and later repairs. Leftover compound keeps if the lid is sealed. Do not let a tidy order tempt you into skipping the waste. A short delivery and a second trip cost time.
- Measure each room on its own and write the sizes down.
- Decide on the sheet size with whoever will carry and hang it.
- Ask your supplier about delivery and about returning unopened pails.
- Check the package for the pail size, the roll length and the coverage.
- Count a second trip if the order is large.
Homes built before 1978
In an older home, joint compound and some other building materials may contain asbestos, and homes built before 1978 may have lead-based paint. This page gives no advice about either. The Environmental Protection Agency publishes information on both; the tool links to its lead and asbestos pages.
Comparing bids per square foot
A bid is easier to read as a price per square foot of drywall. Enter two to four bids and the square feet each one covers, and the calculator divides for you. A 600 square foot bid and a 500 square foot bid are only comparable once both are turned into the same unit.
A low bid can leave things out. Before you compare, ask each contractor whether the price includes:
- Hanging the board
- Taping and all the finish coats
- Texture
- Sanding
- Ceilings
- Haul-away of scraps
- Patching and repairs
- Cleanup
Tick what each bid says it covers, and bring the printed sheet so every contractor answers the same questions.
Your answers and your privacy
The calculator runs in your browser. It has no place to type a phone number, an email or an address, nothing you enter is sent to a server, and nothing is saved when you close the page. Print the sheet if you want to keep the numbers.
Frequently asked questions
How many sheets of drywall do I need?
Add up the wall and ceiling area, add the waste, divide by the area of one sheet and round up. For a 12 x 14 foot room with 8 foot walls and a ceiling, on 4 x 8 sheets with 10 percent waste, the answer is 21 sheets.
Why does the calculator not subtract doors and windows?
Cutting around openings leaves scraps that are hard to reuse, and seams usually land on framing. Keeping the openings in the area works as a built-in cushion. You can lower the waste if your room is mostly openings.
How much joint compound do I need?
The calculator uses about 9 gallons per 1,000 square feet of drywall, a maker's published rate, and rounds up to 4.5 gallon pails. A 584 square foot job needs about 5.256 gallons, which is 2 pails.
How much tape and how many screws?
Paper tape is about 370 feet per 1,000 square feet, in rolls of 250 feet. Screws are about 1 per square foot of board. That is a common rule of thumb and a typed assumption, so check the package and ask your supplier.
Which sheet size should I pick?
Longer sheets have fewer seams but are heavy and awkward to move. Try 4 x 8, 4 x 10 and 4 x 12 in the calculator and see how the count changes, then think about how you will carry them.
Is this a quote?
No. It is an estimate based on the numbers you type. A quote comes from a drywall installer or a supplier who has seen the job. We never show a price we did not source.
Does it work for a ceiling only or walls only?
Yes. Pick ceiling only or walls only and the calculator counts just that surface. For a walls-only room 10 x 10 feet with 8 foot walls and 10 percent waste, it shows 11 sheets.
Do I have to give a phone number or email?
No. There is no place to enter one, and nothing you type is sent anywhere.