Fence Calculator

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Stepped vs Racked Fence Calculator

Plan a fence on sloping ground: slope, length and the drop at each post.

Units
ft
ft
ft

Your result

Enter your numbers and press the button. Your result appears here.

Stepping leaves triangular gaps under each section; racking leaves none but needs panels or pickets that can follow the slope.

How the slope is worked out

Slope = height change ÷ horizontal run. Length along the ground = √(run² + rise²). Step per section = height change ÷ number of sections.

Example: a 48 ft run that drops 4 ft is a 8.3% slope. Stepped in 8 ft sections, each section drops 8.0 in.

Slope by height change at a glance

Worked out with the same settings as the calculator above, changing only the height change.

Height changeSlopeAlong the groundStep per section
1 ft2.1%48.0 ft2.0 in
2 ft4.2%48.0 ft4.0 in
4 ft8.3%48.2 ft8.0 in
6 ft12.5%48.4 ft12.0 in

Common questions

Stepped or racked?

Stepped fences have level sections that drop at each post and leave triangular gaps underneath. Racked fences follow the ground but need panels or pickets that can be angled.

Do I need more fence on a slope?

Slightly. The length along the ground is longer than the flat distance, though the difference is small on gentle slopes.