How the calculators are built
Our calculators use straightforward geometry and package-based rounding rather than hidden scoring models.
General approach
Project dimensions are converted into area or volume, a user-controlled waste allowance is added where appropriate, and the result is converted into the unit a material is commonly purchased in.
Product-specific inputs
Coverage, yield and package size can vary. Whenever possible, users should replace the default values with the numbers on the actual product label or technical data sheet.
Rounding
Boxes, bags, panels and whole-gallon purchase quantities are rounded up because partial packages are often not practical to purchase.
Limitations
Complex geometry, jobsite conditions, workmanship, local requirements and manufacturer instructions can change the real quantity needed. The tools are intended for planning and comparison, not final takeoff or professional design.