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Drywall Calculator

Sheets, mud, tape, screws — the whole order in one pass.

Drywall estimates fail in two places: forgetting the ceiling and under-buying mud. This calculator nets out doors and windows, adds the ceiling if you want it, applies 10% cutting waste, then converts the area into sheets, 500-ft tape rolls, gallons of ready-mix, and pounds of screws — a complete shopping list, not just a sheet count.

Why people use this

Remodelers use it the night before the supplier run: sheets are only half the order — mud, tape, and screws are what get forgotten. The editable cost section doubles as a homeowner's sanity check against a drywall sub's quote.

How it works

1. Enter room length, width, and wall height, plus door and window counts (21 and 15 sq ft deducted each).
2. Choose whether to include the ceiling and pick 4×8 or 4×12 sheets (12-footers mean fewer butt seams).
3. Read sheets (with 10% waste), tape rolls, compound gallons, and screw weight.
4. Open the cost section for a materials-plus-labor estimate with editable unit prices.

Common questions

How much drywall mud do I need per sheet?

A reliable rule is about 1 gallon of ready-mix joint compound per 100 square feet of wall for tape plus two finish coats — roughly 1.5 gallons per 4×8 sheet. Buy one extra gallon; running out mid-coat is worse than returning an unopened one.

Is 4×12 drywall worth it?

On walls longer than 8 feet, yes: 4×12 sheets eliminate butt joints, which are the hardest seams to hide. They are heavier and harder to maneuver in tight stairs and hallways — for small rooms, 4×8 sheets are easier to handle.

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