How much do I need?
Free calculators for home projects. Enter your measurements and get exactly what to buy, with every assumption shown.
Paint Calculator
Gallons and quarts for walls and ceiling, by room size and coats.
Mulch Calculator
Bags or cubic yards for a bed, by size and depth.
Concrete Calculator
Bags of 40, 60 or 80 lb mix, or cubic yards, for a slab.
Tile Calculator
Tiles and boxes for a floor, with extra for cuts.
Drywall Calculator
Sheets of 4x8 or 4x12 for walls and ceiling, plus screws.
Why buy a little extra
Every calculator rounds up and adds a margin for cuts, spills and uneven surfaces. Running out halfway through costs more time than a leftover bag, and later batches of paint and tile rarely match exactly.