Construction Calculator - Framing and Woodwork

Fence Picket Calculator

Estimate pickets or vertical boards from fence length and spacing.

Reviewed: August 26, 2026

Calculate Fence Picket

For the Fence Picket Calculator, enter total run length, picket width, clear gap, and extra allowance. It converts the fence run to inches, divides by picket width plus clear gap, applies allowance, and rounds up to whole pickets.

Construction measuring tools arranged beside a residential building project

Formula and input notes

Pickets = ceil([(run in inches + gap) ÷ (picket width + gap)] × allowance factor)

InputPractical note
Clear gapThis is the Fence Picket Calculator layout value for clear gap; confirm whether the drawing specifies clear or on-center spacing.
Fence Picket Calculator measurement plan showing Total run length feet, Picket width inches, Clear gap inches

Worked fence picket example

Fence Picket Calculator example: The repeated pitch is 3.5 in + 2 in = 5.5 in. Across 127 ft, the layout count is 278; after 5% allowance, order 292 pickets.

Use the count as a baseline

Lay out each bay separately so end gaps are balanced, then round the total to whole boards and account for unusable defects.

Posts, gates, and field conditions

Posts, gate leaves, overlapping patterns, board-on-board coverage, end gaps, shrinkage, curves, and balanced bays change picket count.

Questions specific to this calculation

How do picket width and clear gap combine?

Enter total run, actual picket face width, and desired clear gap. The formula fits repeated picket-plus-gap pitches and then adds allowance.