A straight fence material estimate is easiest when the run is separated into spans and repeating pieces. Posts sit at the ends and between spans, rails are counted per span, and pickets are estimated from their face width plus the clear gap.
This guide covers one open straight run. Gates, corners, changes in direction, shared posts, terminal hardware and cut sections can change the takeoff, so handle those segments separately instead of adding every run as though it had independent endpoints.
Define the straight fence run
Prepare the layout before entering dimensions:
- Measure the uninterrupted run in feet from the first end post location to the last end post location.
- Choose the intended maximum span in feet from the fence system or project plan.
- Mark gates and corners outside this simple run so their posts are not counted twice.
- Confirm whether adjacent runs share a corner post before combining separate estimates.
The post formula uses whole spans. If the run is not an exact multiple of the chosen span, the ceiling function creates one final shorter span and adds the two endpoint positions through the “plus one” post rule.
Measure the repeating parts
Spans = ceiling(run length ÷ span length). Posts = spans + 1. Rails = spans × rails per span. Pickets = ceiling(run length in inches ÷ (picket face width + clear gap)).
What each fence input represents
| Material | Input | Counting rule |
|---|---|---|
| Posts | Run length and planned span | One post at each end plus one at each span boundary. |
| Rails | Rails per span | Multiply the number of whole spans by rails per span. |
| Pickets | Face width and clear gap | Use the repeating installed module in inches, then round up. |
| Gates and corners | Separate segment layout | Review shared and terminal posts before adding quantities. |
Use the picket face width, not a nominal board label that includes a different dimension. The calculator treats the gap as the clear space between adjacent pickets. Check the actual fence system for end returns, trim pieces and installation limits.
Calculate the material list
A straight run becomes spans and repeating picket modules
Worked example: a 48 ft open straight run
- Inputs
- The run is 48 ft, the planned span is 8 ft, the fence uses 2 rails per span, and each picket is 5.5 in wide with a 0.5 in clear gap.
- Calculation
Spans: ceiling(48 ÷ 8) = 6. Posts: 6 + 1 = 7. Rails: 6 × 2 = 12. Picket module: 5.5 + 0.5 = 6 in. Pickets: ceiling(48 × 12 ÷ 6) = ceiling(96) = 96.- Result
- 7 posts, 12 rails and 96 pickets
The independent calculation matches the three calculator modes. The run divides evenly, so no partial final span is created. Add separate gate, corner, hardware and packaging quantities only after the actual layout is known.
Check the run in the Wood Picket Fence Material Calculator.
Start the layout record with the yard measurement guide.
For a straight run made from prefabricated panels, use the Prefabricated Fence Panel Layout Calculator.
Conclusion
Count whole spans first, place one more post than the span count, multiply rails per span and divide the run by the installed picket module. For the 48 ft example, the straight-run estimate is 7 posts, 12 rails and 96 pickets before separate gate, corner and package rules.