Drywall Calculator
Room length, width, and wall height in — or the square footage straight up if you already have it. Doors and windows come off, the ceiling goes on if you're boarding it, and out comes the sheet count for your board size plus the finishing order: screws, joint compound, and tape.
Planning tool — results are estimates for quoting and ordering, not engineering or building-code advice.
Common questions
How many sheets of drywall do I need?
Total the wall area (perimeter × height), add the ceiling if you're boarding it, subtract about 21 sq ft per door and 15 per window, add waste, and divide by the sheet: 32 sq ft for 4×8, 36 for 4×9, 40 for 4×10, 48 for 4×12. The calculator rounds up — you can't hang half a sheet you didn't buy.
How much mud, tape, and screws per sheet?
Standard estimating rates: about 1 screw per square foot on 16" o.c. framing, 0.053 lb of ready-mix compound per square foot for tape and finish coats, and 0.375 ft of tape per square foot (a 500' roll finishes roughly 1,300 sq ft). Rough figures for ordering — texture and higher finish levels take more mud.
What waste factor should I use?
10% covers regular rooms with standard-height walls. Go 15% or more for cut-up rooms, angles and stairwells, or 9'+ walls hung with 4×8 board — longer sheets that run the wall in one piece waste less, which is why they're worth the awkward carry.
Related: Stairkey for drywall contractors · Free drywall estimate template · Paint calculator
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All 14 are free, feet-and-inches in, no sign-up. Pick the next one for the job.
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Finishes & materials
This solves one measurement. The Takeoff Builder prices the whole job.
Walk the rooms, enter dimensions, and formula-driven scope turns measurements into quantities, prices, and the estimate itself — from $20/mo, capped, no surprise bills.