Home Improvement Calculators

How these estimators work

• Each tool uses simple geometry and common DIY planning rates (for example roof pitch factors, board-foot lumber math, ~350 sq ft of paint coverage per gallon per coat, or ~1.4 tons of gravel per cubic yard). Assumptions are listed on every calculator page.
• We round purchasable counts up—whole gallons, bags, tiles, boxes, sheets, squares, and pickets—because you cannot buy a fraction of a sealed bag at the store.
• Where cuts, spillage, or uneven grade are normal (roofing, concrete, tile, flooring, drywall), we apply a waste factor (often about 10%) before rounding so your order includes a practical buffer.
• These are planning estimates for rectangular rooms, beds, and straight fence runs. Irregular shapes, textured surfaces, and manufacturer labels can change the final quantity—confirm against the product you buy.