Fence Calculator - Calculate Posts, Rails, Pickets, and Concrete
Free fence calculator. Calculate posts, rails, pickets, and concrete bags for privacy, picket, or rail fences. Includes gate calculations.
Fence Dimensions
Terrain & Layout
Extra post per corner
Where fence terminates
Inches of rise per 8ft fence section
Enter fence dimensions to see results.
About This Calculator
How to Calculate Fence Materials Needed
Measuring Tips
- Measure the total linear feet of your fence line along the property boundary
- Account for corners, gates, and changes in elevation
- Mark post locations with stakes before purchasing materials
- Check for underground utilities before digging post holes
- Add 10% extra for waste, cuts, and mistakes
Fence Type Guide
| Fence Type | Height | Rails per Section |
|---|---|---|
| Picket Fence | 3-4 feet | 2 |
| Rail Fence | 3-4 feet | 2-3 |
| Privacy Fence | 6-8 feet | 3 |
| Pool Fence | 4-5 feet | 2-3 |
Tips for Best Results
- Use pressure-treated lumber or cedar for ground contact posts
- Set posts in concrete for maximum stability and longevity
- Use galvanized or stainless steel fasteners to prevent rust
- Install a gravel base in post holes for drainage
- Check local building codes for height and setback requirements
Frequently Asked Questions
How do I calculate fence materials needed?
Measure the total linear feet of your fence line. Divide by post spacing (typically 8 feet) to get the number of posts. Add one extra post for the end. Multiply linear feet by the number of rails per section (usually 2-3) to get total rail length. For pickets, divide linear feet by picket width plus spacing to get the count.
How far apart should fence posts be?
Standard post spacing is 8 feet on center for most fence types. For privacy fences or areas with high wind loads, 6-foot spacing provides extra strength. For lightweight rail fences, posts can be spaced up to 10 feet apart. Always check local building codes for requirements.
How many concrete bags do I need per post?
For a standard 4×4 post, you need approximately one 80 lb bag of concrete for a 2-foot deep hole. For 6×6 posts or deeper holes (3+ feet), use 2 bags per post. The hole should be 3 times the post width and 1/3 the post length below ground.
What is the standard picket spacing for a fence?
Standard picket spacing is equal to the width of one picket, typically 3-1/2" for a standard 1×4 picket. For a privacy fence with no gaps, pickets are installed tight together. For decorative spacing, use a spacer block equal to the picket width for consistent gaps.
How many rails do I need for a 6-foot fence?
A standard 6-foot fence typically uses 3 rails per section: one at the top, one at the bottom, and one in the middle. For fences under 4 feet, 2 rails are usually sufficient. The rails are typically 2×4 lumber spanning between posts.