Decking Calculators
Build the perfect deck with our free decking calculators. Work out exactly how many deck boards you need, the correct joist spacing for a solid sub-frame, and the overall materials for your project.
Whether you are using timber or composite boards, these tools handle the maths so your deck is strong, level and built without costly over-ordering. All calculators support metric and imperial units.
Decking Calculators(6)
Deck Calculator
Calculate decking boards, joists, posts, and hardware for building a deck.
Deck Board Calculator
Calculate how many deck boards you need based on deck size, board width and the gap between boards.
Deck Joist Spacing Calculator
Calculate the number of deck joists, spacing and total joist length for your decking frame.
Decking Screw Calculator – How Many Decking Screws Do I Need?
Work out how many decking screws you need and how far apart to space them, based on your deck size, board width and joist centres.
Decking Cost Calculator
Estimate the cost of a deck from the deck area, board price and optional joist, post and fixings costs.
Baluster Spacing Calculator
Work out evenly spaced balusters or spindles for a railing while keeping gaps within the 100mm (4in) safety limit.