Calculapedia

Fence Calculator

How much fencing do you need? Enter your run length for panels, posts, and cost.

Posts needed
Rails (3 per section)
Estimated cost
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How this calculator works

It divides your fence run by the panel width to get the number of sections, then adds one post per section plus a final end post, and three rails per section.

Worked example — a 100 ft fence with 8 ft sections:
100 ÷ 8 = 13 sections → 14 posts and 39 rails.

Don’t forget gates and corners

Each gate and corner usually needs an extra, heavier post. Add those to the post count above before you buy.

Frequently asked questions

How far apart should fence posts be?

Most wood and vinyl fences use 6–8 ft spacing between posts.

How many posts for a 100 ft fence?

At 8 ft spacing, about 14 posts (sections plus one end post).

Planning an outdoor project

Outdoor quantities vary with site shape, access, drainage, soil conditions, and local material availability. Break irregular areas into simple sections, confirm the product specification with your supplier, and check permits or utility requirements before starting work.

How to use this estimate

Accuracy and limitations

Calculapedia provides educational planning estimates. It does not inspect your site, select products, guarantee quantities, or replace a contractor, engineer, architect, building official, or supplier. Confirm the final quantity and any safety or code requirements before buying or building.

Add this calculator to your site — free

Paste this code onto any web page (blog, forum, business site). It always shows the latest version and links back here.