Free carpentry & framing calculators

Instant results, live diagrams, no signup. Built for people measuring on site with a tape in one hand and a phone in the other.

Stair calculator

Riser height, tread depth, total run, stringer length and angle with IRC code checks.

Pitch, angle, grade, slope factor, rafter and hip lengths with IRC material checks.

Rafter length, birdsmouth seat and HAP, plumb cut, rafter count and lumber to buy.

Boards to buy by stock length, last-row rip, butt joints on joists, screws or clips.

Coming soon

Stringer layout, cut marks and board length.

Coming soon

Post spacing, depth and concrete volume.