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Use this free fence calculator to find out exactly how many posts, panels, and concrete bags your project needs — before you head to the store. Choose your material type, enter your yard dimensions one side at a time, and add gate openings if your fence includes them. The calculator adjusts post spacing, panel count, and concrete requirements based on whether you’re building with wood, vinyl, or chain link.
Fence Calculator
Enter your yard dimensions to get post count, panel count, and concrete bags.
Standard 8 ft panels · Posts every 8 ft
Enter the length of each side of your yard. Add as many sides as your yard has — most yards have 4, but irregular lots may have more.
Please enter at least two side lengths to calculate.
How the Fence Calculator Works
Enter the total length of your fence line, your post spacing, and your panel width, and the fence calculator works out how many posts, panels, and bags of concrete you need. Most wood and vinyl fences use posts every 6 to 8 feet. The calculator divides your fence length by that spacing and adds one post for the end. Add extra fence posts for each corner and gate.
Measure the fence line with a tape or measuring wheel and walk the whole route before you buy anything. Mark where every gate will go, since gates need a post on each side, and the hinge side needs to carry the gate’s weight. If your yard slopes, measure along the ground, not straight across, and plan for stepped or racked panels.
What You’ll Need to Set Your Fence Posts
Once you know your post count and concrete bags, here’s what to grab before you start digging.
A manual post hole digger handles most residential fence projects without renting equipment — the clamshell style gives you clean, round holes at the right diameter. For anything over 20 posts, consider renting a power auger instead.
For concrete, Quikrete Fast-Setting Concrete Mix is the go-to for fence posts — you pour it dry into the hole, add water, and it sets in 20 to 40 minutes without mixing. No wheelbarrow needed for small jobs.
For larger projects, a 20-gallon concrete mixing tub keeps the mess contained, or step up to a handheld electric cement mixer if you’re setting a full perimeter.
Before the concrete sets, use a post level to confirm the post is plumb on all four sides — it clips onto the post hands-free so you can adjust and pour at the same time. A crooked post at this stage means a crooked fence forever.
For a more detailed look at exactly how much concrete each individual post needs, run your numbers through our concrete per fence post calculator — it accounts for hole diameter, depth, and bag size.
If you’re adding gravel around post bases or along the fence line for drainage, our gravel calculator will tell you exactly how many tons or cubic yards to order.
Planning hardscape beyond the fence? Our guide on how to fix a sinking patio covers base problems that affect any outdoor structure set in the ground.
Frequently Asked Questions About the Fence Calculator
How many fence posts do I need?
Divide the length of the fence by your post spacing, then add one. A 96-foot fence with posts every 8 feet needs 13 fence posts, plus extras for corners and gates. The fence calculator above does this for you.
How many bags of concrete do I need per fence post?
Most 4×4 fence posts take about two 50-pound bags of concrete, but it depends on how deep and wide you dig. For an exact count based on your hole size and frost line, use our concrete per fence post calculator.
How far apart should fence posts be?
Most fences space posts 6 to 8 feet apart. Eight feet is common for wood privacy fences, while vinyl panels usually set the spacing for you. Check your panel width before you enter the spacing in the fence calculator.