How much material do you need?

Documented formulas

Estimatorly calculators are built around documented formulas that you can inspect under each result. Volume tools convert length, width, and depth into cubic feet or cubic yards. Coverage tools multiply surface area by coats and divide by a stated coverage assumption. Unit-count tools use the product-size assumption shown in the calculator, and cost tools multiply the quantity by the applicable material or installation rate.

U.S. customary units

This version uses feet and inches for dimensions, pounds for weight, gallons for liquids, cubic yards for bulk volume, and tons for aggregate or asphalt. Enter measurements in the units shown beside each field. Choices such as thickness, spacing, waste, coats, or material type change the result and the “Show the math” explanation.

Rounded-up order quantities

Purchase quantities are rounded up whenever a supplier sells a whole unit. You cannot buy 12.4 bags, 8.2 boards, or part of a roll, so the calculator separates the mathematical quantity from the practical quantity to order when that distinction matters. A waste allowance is a documented assumption, not a guarantee that every project will use the same amount.

Planning ranges, not quotes

Prices are shown as 2026 U.S. national planning ranges where verified source data is available. Local supplier pricing, delivery, labor, taxes, regional demand, product grade, site access, and seasonal conditions can change the final number. Confirm current price and availability locally before buying.

These results are planning figures, not contractor quotes, engineering designs, code determinations, or guarantees of material performance. Use them to compare quantities and prepare better questions for a contractor or local building department. For structural, drainage, load-bearing, or permit-sensitive work, follow project plans and applicable local requirements.