Most home projects need one measurement and one rule: quantity = area or volume × (1 + waste) ÷ coverage per unit. For example, 180 sq ft of floor with 10% waste and 20 sq ft boxes means 10 boxes. Pick a calculator below for paint, flooring, concrete, landscaping, roofing, insulation and lumber.
Paint & Walls
Flooring & Tile
Concrete & Masonry
Landscaping
Roofing & Exterior
Insulation & Lumber
Why SimpleHomeCalc
Each calculator lets you switch between feet and meters, adds a waste factor, rounds up to the units stores sell, and totals the cost if you enter a price. Formulas and assumptions are printed on every page with sources.
Frequently asked questions
Are the calculators free?
Yes, all of them, with no sign-up.
Do you store my measurements?
No. Everything runs in your browser.