Deck Calculators

Size boards, joists, beams, posts and footings, then price the build out.

10 free deck calculators — no sign-up, instant results.

Composite Deck Calculator

Calculate composite decking boards and material cost for your deck project.

Calculate beam size and quantity needed to support deck joists for your deck span.

Calculate the number of deck boards needed to cover your deck surface, accounting for board width, length, gaps, and waste.

Calculate total deck project cost including materials, labor, waste, and taxes.

Calculate concrete volume and bags needed for deck footing holes below the frost line.

Calculate the number of joists needed for deck framing based on span length and spacing requirements.

Calculate all materials needed for deck construction including boards, joists, posts, and footings.

Calculate the number and size of posts needed for deck support based on deck dimensions and height.

Calculate deck stair dimensions including riser height, tread depth, and step count for safe stairs.

Calculate decking material quantities for composite and pressure-treated deck surfaces, with waste allowance.