Fence Material Calculator
Estimate posts, sections, rails, pickets, post length, and concrete for a straight fence run.
Fence inputs
Live material estimate
Estimate ready: 14 posts, 39 rails, 178 pickets, and 1.33 cubic yards of concrete.
Material breakdown
| Material | Calculation basis | Estimated quantity |
|---|---|---|
| Posts | Ceiling(100 ÷ 8) + 1 | 14 |
| Sections | Posts – 1 | 13 |
| Rails | 13 × 3 | 39 |
| Pickets | Ceiling(1,200 ÷ 6.75) | 178 |
| Concrete | 14 cylindrical holes less post displacement | 1.33 yd³ |
Quantities are planning estimates for one continuous straight run. Gates, corner bracing, waste, terrain changes, local code, frost depth, and site-specific engineering are not included.
How to use this fence material calculator
What this calculator does
This calculator converts a proposed straight fence layout into a material takeoff for posts, sections, rails, pickets, required post length, hole diameter, and concrete volume. It is useful for early budgeting, comparing layouts, preparing a shopping list, and checking how spacing decisions change quantities. It does not determine structural adequacy, property boundaries, utility locations, frost-depth compliance, permit requirements, gate hardware, or wind-load design.
When to use it
Use it when planning a new privacy fence, replacing a damaged straight run, comparing six-foot and eight-foot post spacing, or estimating how many bags or bulk concrete to order after the fence geometry is established.
How to calculate
- The calculator opens with a complete 100-foot demonstration fence and a validated Excel workbook ready to download.
- Replace each sample value with your project dimensions. Use feet for overall fence dimensions and inches for picket and post dimensions.
- Read the live result cards and the material breakdown table. Counts are rounded upward because partial posts or pickets cannot complete the run.
- Select the correct Post shape. For a round post, Post thickness is ignored; for a square or rectangular post, both dimensions are used.
- Choose Download Excel to save the current typed inputs and outputs. Reset clears the demonstration and all results; Download Excel then remains unavailable until every required value is complete and valid again.
Input guide
Fence length is a required positive decimal in feet, such as 100. Increasing it raises every quantity. Do not enter perimeter segments that include gates unless you intend to treat those openings as fence. Post spacing is a required positive distance in feet, commonly 6 – 8 feet for many residential layouts; smaller spacing raises the post and section counts. The calculator treats it as a maximum and rounds the number of spaces upward. Fence height is the required above-grade height in feet. The model uses a post length equal to 1.5 times the fence height, matching the one-third-buried relationship used by the reference formula.
Rails per section is a required whole number, for example 3; it multiplies directly by the number of sections. Picket width and Picket spacing are required positive inch values. Their sum is the repeating pitch, so wider pickets or larger gaps reduce the count. Avoid confusing nominal board size with actual face width. Post shape determines whether displaced post volume is rectangular or circular. Post width / diameter is required in inches and also sets the assumed hole diameter at three times the post width. Post thickness is required only for square or rectangular posts and affects the concrete displaced by the buried post.
Output guide
Posts is the rounded-up number of spaces plus one end post. Fence sections is always one fewer than the post count. Post length includes the assumed buried portion. Total rails equals rails per section times sections. Total pickets is the fence length in inches divided by picket pitch, rounded upward. Hole diameter is a planning assumption of three post widths. Concrete volume is the sum of cylindrical hole volumes less the buried post volume, shown in cubic yards. A zero or missing result means the inputs are incomplete or invalid, not that no material is required.
Worked example
For the startup example, a 100-foot fence with 8-foot maximum post spacing needs ceiling(100 ÷ 8) + 1 = 14 posts and 13 sections. With 3 rails per section, the rail count is 39. A 5.5-inch picket plus a 1.25-inch gap creates a 6.75-inch pitch; 1,200 ÷ 6.75 rounds up to 178 pickets. A 6-foot fence produces a 9-foot post, with 3 feet buried. For 4-by-4-inch posts, the assumed holes are 12 inches in diameter. Subtracting the buried post displacement from all 14 cylindrical holes gives approximately 1.33 cubic yards of concrete.
Learn more
For post-hole planning, review QUIKRETE's guidance on a hole diameter about three times the post width and a depth related to the above-ground height in its setting posts in concrete instructions. For exact customary-to-metric factors, consult the NIST unit conversion tables.
Formulas and planning assumptions
Posts = ceiling(Fence length ÷ Post spacing) + 1
Sections = Posts – 1
Rails = Sections × Rails per section
Pickets = ceiling(Fence length in inches ÷ (Picket width + Picket spacing))
Post length = 1.5 × Fence height
Concrete is modeled as a circular hole whose diameter is three times the post width. Hole depth is one-half of the above-grade fence height, which corresponds to one-third of the resulting total post length. The buried post volume is subtracted from the hole volume. Actual excavation and concrete orders should be adjusted for frost depth, drainage gravel, bell-shaped holes, soil collapse, slope, corners, gates, and jobsite waste. Local building departments and utility-location services should be consulted before digging.
Buying a modest material allowance can cover cuts, defects, breakage, and future repairs. Apply that allowance after reviewing the exact product lengths and package sizes available from your supplier rather than automatically adding it to every line item.