Plaster Calculator
Enter your size to get plaster quantity, plus an estimated cost. Waste is included and prices are editable.
Material needed
Estimated cost
How to calculate plaster
Plaster material by the square foot. Enter wall area to get square feet.
Formula: quantity = area × 1 × (1 + waste %) = 100 × 1 × 1.10 = 110 sq ft.
Worked example
Example: 10 ft × 10 ft = 100 sq ft. Quantity: 110 sq ft, about $220 at $2 per sq ft.
Tips
Measure the full area, then subtract large openings if you want an exact count. Order a little extra for cuts and breakage, and confirm quantities with your supplier before you buy.
Related calculators
Frequently asked questions
How much plaster do I need?
Example: 10 ft × 10 ft = 100 sq ft. Quantity: 110 sq ft, about $220 at $2 per sq ft.
How much waste should I add?
Add 10% for straight areas and 15% for areas with many cuts, corners and openings.
Are the prices accurate?
Prices are editable estimates. The defaults are typical US figures, and your local price can be higher or lower.