Measure the run
Measure each straight run between post centers. Choose a shared start only where it meets a previous run’s end post. Enter each gate’s position and post-center opening width on its own run.
Tool Switcher: Fence
Project toolsTools
Fence planning tool
Fence Calculator
Combine wood fence runs, connect shared corner posts, and place gates to estimate posts, rails, pickets, concrete, fasteners, and material costs.
- Posts, rails & pickets
- US and metric units
- Full material ticket
Fence planning tool
Fence Calculator
Plan wood fence runs, shared corner posts, gates, and material costs.
Methodology
From fence layout to a material ticket
Divide into sections
Split each run at its gate openings. For every remaining fenced interval, sections = ceiling(interval length ÷ post spacing). Gates interrupt rails; rounding is per interval, never on a combined net length.
Count posts, rails, and pickets
Count every unique endpoint and gate boundary once, then add sections − 1 internal posts per fenced interval. Gate posts are included in that total. Rails = sections × rails per section. Exact pickets = combined fenced length in inches ÷ (picket width + gap).
Plan concrete and fasteners
Purchased pickets = ceiling(exact pickets × (1 + allowance ÷ 100)). Concrete = ceiling(posts × your bags per post); screws = purchased pickets × your screws per picket. Blank material prices stay unpriced.
Worked example
A 100 ft run with 8 ft post spacing
100 ftfence run
÷8 ftpost spacing
=13 sections14 posts
From 13 sections, this run needs 14 posts, 39 rails, 240 pickets, and 28 bags of concrete. The 10% allowance applies only to pickets: 218.18 exact becomes 240 purchased. Three rails per section, two bags per post, and six screws per picket are example settings.
A corner and a gate change the post count
Two 16 ft runs with 8 ft spacing need four sections. If they share one corner post, buy five posts; if they are independent, buy six. For a 100 ft run with a 4 ft opening starting 48 ft from the start, the two fenced intervals are 48 ft each: 12 sections and 14 posts, including the two gate posts. Moving that opening to 4 ft from the start creates 4 ft and 92 ft intervals: 13 sections and 15 posts.
The tool supports up to 20 straight runs and 20 gates total. Its connection selector joins a run’s start to an earlier run’s end. Branching junctions, gate-only runs, and touching or overlapping gates are rejected. It does not draw a site plan or detect crossing or overlapping runs; confirm those measurements yourself.
Frequently asked questions
A second look at the estimate.
How many fence posts do I need?
Divide each fenced interval between endpoints and gates by your spacing and round up. Count its boundary posts and internal posts, then count a shared endpoint only once. Gate posts are part of the total, not two extra posts added to it.
How many pickets for a 100 ft fence?
Divide the run by the picket pitch (width plus gap), then add a waste allowance. A 100 ft privacy fence with 1×6 pickets takes about 240 pickets at 10% waste.
How much concrete per post?
Enter bags per post from the yield on your concrete product and the hole dimensions specified for your installation. Two bags is a worked-example setting, not a recommendation. This calculator does not choose hole size, depth, or footing design.
Can I enter metric dimensions?
Yes. Metric mode uses meters for runs, spacing, and gates, and centimeters for picket width and gap.
How is the cost estimated?
Enter prices per post, picket, rail, concrete bag, and screw, plus a materials price for each gate leaf and its hardware. The result lists each priced line and shows a subtotal with missing prices. Once every required line is priced, it shows an estimated material cost. Labor, delivery, tax, and other hardware are excluded.
Sources and limitations
This tool estimates fence materials for planning. It does not select post depth, footing design, or gate hardware, and it does not replace local building, zoning, or HOA requirements or retrieve live prices.
- Lowe’s — How to Build a Wood Fence — layout, post spacing, and gate hardware considerations; not a specification for every fence.
- 811 — Before You Dig — locate underground utilities before digging.
- Concrete bag calculator — compare bag sizes for the post-hole concrete.
- Concrete calculator — estimate volume for footings or a slab.
For component-built wood fencing, using level horizontal run measurements and post-center gate opening distances. Matching endpoints share one physical post. The starting spacing, rails, concrete bags, fasteners and allowance are editable worked-example values, not a structural design or universal product specification. Confirm spacing, gate clearances, fastener requirements and concrete yield for your selected products and local conditions. Gate leaf materials are separate from fence pickets and rails.
Last reviewed: October 4, 2026