Fence Calculator
Plan your fence project with confidence. Enter your fence line length, choose your height and style, and this calculator instantly estimates how many posts, rails, pickets, and bags of concrete you'll need โ plus a total material cost. Works for wood privacy fences, picket fences, and shadowbox styles.
๐ Fence Material Estimate
How to Use the Fence Calculator
Start by measuring your total fence line in linear feet. Walk the property line with a measuring wheel or tape โ don't forget to account for gates (subtract gate width from the total, as gates use their own hardware). Enter the length into the calculator along with your desired fence height.
Post spacing is typically 8 feet on center for wood fences, but you can tighten to 6 feet for extra wind resistance or heavier gates. More posts means a stronger fence but higher cost. The post count formula is length รท spacing + 1, which gives you one post at the start and one at each interval.
Rails are the horizontal members that run between posts. A 4-foot picket fence usually takes 2 rails. A 6-foot privacy fence can use 2 or 3 rails (3 is better for preventing sag). An 8-foot fence should always use 3 rails. Each rail is typically a 2ร4 that spans the full post spacing.
Pickets are calculated based on their actual width plus any gap. For a standard privacy fence, use 5.5-inch pickets with 0-inch gap (tight-fit). For a spaced picket fence, add a 1โ2 inch gap for that classic look. The calculator adds 10% extra for waste, cut-offs, and damaged boards.
Concrete: Each post hole takes roughly 2 bags of 50 lb fast-setting concrete mix for a 6-foot fence (hole: 12" diameter ร 30" deep). Adjust to 3 bags for 8-foot posts. The calculator multiplies post count by the appropriate bag factor.
Fence Building Tips
- Call 811 before digging. Utility line locates are free and legally required in most states. Hitting a gas or electric line can be deadly and expensive.
- Set corner posts first. Mark and set all corner and end posts, then run a string line between them to keep intermediate posts perfectly straight.
- Dig below the frost line. In cold climates, post holes should extend at least 6 inches below your regional frost depth. Check local code โ in northern states this can be 42โ48 inches.
- Use galvanized or stainless hardware. Standard steel screws and nails will rust and streak your fence within a year. Spend the extra $20 on coated fasteners.
- Leave a gap at the bottom. Keep pickets 1โ2 inches above grade to prevent rot from ground contact. This also makes trimming and mowing easier.
- Gravel at the bottom of each post hole โ add 3โ4 inches of gravel before setting the post to improve drainage and extend post life.