Fence Panel Calculator

How This Is Calculated

Panels needed is the total run length divided by one panel's width, rounded up. Posts needed is always one more than the number of panels, since a straight run of panels needs a post at both ends as well as between each pair of panels.

Post length to buy is the fence height plus the burial depth, rounded up to the nearest 300mm to match typical stock lengths - this doesn't include any extra allowance for a decorative post cap sitting above the panel, so add a little more if you're fitting one. Gravel boards, when included, match the number of panels, since each bay gets one board along its base.

Common Questions

Why are fence panels almost always 1.83m (6ft) wide?

It's the near-universal standard width across UK fence panel manufacturers, regardless of the panel style or height, so posts, gravel boards and fittings from different suppliers are broadly interchangeable. Height varies (typically 0.9m to 1.8m), but width essentially never does for standard panels.

How deep should a fence post go in the ground?

600mm (2ft) is a common minimum for a standard garden fence, though a deeper hole - sometimes up to a third of the post's total length - is safer for taller fences or exposed, windy sites. Our concrete calculator's fence post mode can work out exactly how much postcrete or concrete a hole of your chosen depth needs.

Why round the post length up to the nearest 300mm?

Fence posts are typically sold in whole-foot stock lengths (roughly 300mm increments), so rounding up to the nearest one reflects what you can actually buy rather than a length that falls between two stock sizes.

Do I need gravel boards?

They're not compulsory, but a gravel board at the base of each panel keeps the panel itself out of contact with the soil, which is where damp and rot set in fastest. It's cheap insurance that noticeably extends the life of the panels above it, and it means only the gravel board needs replacing if the base ever does rot through.