Fence Calculator
Estimate fence boards and posts for a straight or rectangular fence run.
How to measure a fence run
Measure along the ground where the fence line will run, section by section, and add them up. Include gate openings in the total — we subtract them for boards but posts still frame them.
How we calculated it
We take your total fence run, subtract gate openings, and divide by the width of one board plus its gap to count boards. Posts come from your post spacing — total run divided by spacing, plus one to close the run.
Things that can change your result
- A “6-inch” picket is really 5.5″ — nominal vs. actual lumber sizes change the count.
- Board-on-board and shadowbox styles overlap boards and need substantially more than this straight-run count.
- Corners and gate frames each add posts beyond the straight-run estimate.
Buying tips
- Buy 5% extra boards — lumber piles always include a few warped or split ones.
- Concrete for post holes is its own estimate — our concrete calculator handles it.
- Call 811 before digging post holes.
Common mistakes
- Counting with nominal board widths.
- Forgetting that each corner needs its own post.
- Setting post spacing wider than the rails can span.
Frequently asked questions
How many fence boards per foot?
With 5.5″ boards butted tight, about 2.2 boards per linear foot; a half-inch gap drops it to 2 per foot.
How far apart should fence posts be?
8 feet is standard with 8-foot rails; heavy panels or windy sites sometimes use 6 feet.
How many bags of concrete per post?
Usually one to two 50 lb bags per post depending on hole size — our concrete calculator can check your exact hole dimensions.