Home & Construction Calculators

Free home and construction calculators — square footage, materials like gravel, asphalt and lumber, plus framing and wiring. Instant, no signup.

ziffaro’s home and construction calculators handle the measuring and estimating that comes with a project — before you order materials or pick up a tool. Work out the square footage of a room or lot, how many tons of gravel or asphalt a job needs, how many board feet are in your lumber, the length of a roof rafter, or the voltage drop on a wire run. Each tool takes plain measurements, converts the units for you and shows the result instantly in your browser — free, with no signup. The estimates are a solid starting point for ordering and budgeting; for code-regulated electrical work and structural spans, confirm against the relevant code and a licensed pro before you build.