Drywall Mud Calculator
Plan joint-finishing supplies from board area or sheet count. Choose a documented ready-mix rate, enter package sizes, and print your shopping quantities.
Estimate joint compound and drywall tape
Enter the surface area that will actually be finished, or count sheets and specify their area. Include exposed walls and ceilings once. Do not multiply by hidden board layers or include cutting waste from unused sheets. Area mode ignores the sheet inputs; sheet mode ignores the total-area input. Changing units reinterprets the numbers, so update both area fields as needed.
How the estimate works
Compound = finished area in square feet ÷ 100 × selected gallons-per-100-square-feet rate. Tape uses the same area with your editable tape rate. Extra material is applied once to each quantity. Divide by the container or roll size and round up separately; the price estimate uses the whole containers you buy.
Worked example
For 1,000 square feet with the all-purpose example and 10% extra, estimate 11 US gallons of compound and 407 feet of tape. At 3.5 gallons per container and 250 feet per roll, buy 4 containers and 2 rolls. At 20 per container and 5 per roll, the estimated material cost is 90.
Are all compounds interchangeable?
No. The example rates are based on USG installation guidance for typical joint finishing. Custom mode accepts another ready-mixed product's documented volume rate. Dry setting compound sold by weight needs its manufacturer's mixed yield; a bag weight cannot be entered as gallons. The tool does not determine finish level, skim-coat coverage or the number of coats.
Why is tape only an estimate?
The 37-feet-per-100-square-feet starting rate is an area-based planning allowance. Board orientation, corners and seam layout change actual tape length. Edit it using your measured joint length or supplier guidance. Small repairs and full-surface skim coating need a different estimate.
Can I use square metres?
Yes. Board area is converted to square feet internally. Results show litres and metres alongside US gallons and feet. Container and roll inputs retain their explicitly labelled units. Prices are user-entered and exclude tax, labour and delivery.
Reference: USG Sheetrock estimator and CGC/USG installation guide J371. Rates are planning examples, not endorsements.
Related: Drywall Sheet Calculator · Paint Calculator
Reviewed 4 November 2026. Free, no signup. Inputs stay in your browser. Quantities are estimates; check measurements and product instructions before purchasing.