What does this tool do?
A fence is divided into equal bays by its posts, so the post count is one more than the number of bays. Rail length is the number of bays multiplied by the rails per bay and the post spacing.
The Formula
Bays = ⌈Fence length ÷ Post spacing⌉; Posts = Bays + 1; Rail length = Bays × Rails per bay × Post spacingFrequently Asked Questions
How far apart should fence posts be?
8 ft is common for timber panels, while 6 ft suits heavier or taller fences. Always follow the panel manufacturer and local wind-load rules.
Do I need extra posts for gates?
Yes. Gate posts carry more load and are usually set deeper in concrete, so add them separately from the line-post count.