Home Improvement
Paint Calculator
Estimate wall area, multi-coat coverage, exact gallons, and a rounded-up paint purchase quantity.
Drywall Calculator
Estimate drywall sheets from known area or four walls plus the ceiling of a rectangular room.
Choose a transparent area method and see theoretical and rounded-up sheet quantities.
Enter your details
Drywall coverage details
Total drywall areaArea per sheetSheets before wasteSheets after wasteRounded-up purchase quantity
Your estimate will appear here
Complete the fields and calculate to see a detailed result.
Two transparent methods
Surface mode uses your total. Room mode calculates four walls plus ceiling without subtracting openings.
Formula and methodology
Room area is 2 × (length + width) × height + length × width. Sheet area is length × width. Area ÷ sheet area gives theoretical sheets; waste is applied before rounding up.
Worked example
A 12 by 10 by 8 ft room has 472 sq ft. With 32 sq ft sheets, 14.75 is theoretical; 10% waste gives 16.23, rounded to 17.
Assumptions and limitations
Openings, soffits, layers, orientation, offcuts, ratings, framing, fasteners, and structural requirements are not estimated.
Frequently asked questions
Which mode should I use?
Use measured area for complex projects.
Are openings subtracted?
Not in room mode.
Does this estimate framing?
No; it estimates sheets only.
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Home Improvement
Flooring Calculator
Estimate base room area, a selected waste allowance, and total flooring square footage.