Deck board calculator for iPhone

For parallel board runs across a rectangular deck. The run length follows the boards; the cross width determines how many courses fit.

Deck and boards

Run length, cross width, actual board width and internal clear gap.

Purchase inputs

Available stock board length and, optionally, price per board.

Full first board starts with an untrimmed board when the deck width allows it, then resolves the final edge. Balanced edges shares the width between the first and last boards. If only one course fits, it is trimmed to the deck width.

• Course count, first and last board widths, the clear gap, installed run length and deck area. Any free space after the last board is shown separately.
• Purchased board count, whether end joints are required and optional total cost.

Balanced edges, with stock boards twice the run length and no allowance for saw kerf.

Course count = ceil((cross width + gap)/(board width + gap)). Twelve middle boards use 1680 mm; thirteen gaps use 65 mm. The remaining 255 mm is split between the two edges. Each 6 m stock board provides two 3 m runs in this ideal length model.

Metric and imperial entry are available. Gap size comes from the selected material and installation conditions; this calculator does not prescribe it. Use actual board width, not the nominal trade size.

Purchase arithmetic does not include saw kerf, trimming allowance, joist design or a complete joint layout. If stock is shorter than a course, the result flags joints and counts stock pieces per course.

Does balancing change the number of courses?

It changes the edge-width distribution. The physical course count and actual edge widths remain visible so you can compare the two layouts.

Is installed length the shopping quantity?

No. Stock length determines how many complete runs can be cut from a board. Allow separately for the real cutting process.