Concrete for Fence Posts Calculator

Hole volume minus buried post volume, times post count, divided by bag yield — rounded up once for the whole project. Uses the same calculation function as the visual planner.

Editable hole diameter and depth
Actual square post face for displacement
Editable bag yield (planning default 0.33 cu ft)
Optional contingency/waste (off by default)

Hole depth is an editable assumption. Frost depth is local — verify before digging. Enter the yield printed on your selected product; the default is not a brand or bag-weight fact.

Units

Number of concreted postsHole diameter (in)Hole depth (in)Post face used by this plan (in)Enter the measured or manufacturer face — not a guaranteed nominal size.Concrete yield (cu ft per bag)Planning default is 0.33 cu ft — enter the yield on your product label.

Apply contingency / waste %Waste %

Results

Cylindrical hole volume (each): 2.36 cu ft
Displaced buried-post volume (each): 0.33 cu ft
Net concrete per post: 2.02 cu ft
Net calculated project volume: 8.09 cu ft
Exact bags before rounding: 24.52
Whole bags to purchase: 25

Rounding is one project-level ceiling on total volume ÷ bag yield. Hole size, post face, and bag yield are editable assumptions — not frost, soil, or code requirements.

Open visual planner Methodology

Planning estimates only. Verify product dimensions, permits, and site conditions before building.