Saw kerf, edge trim & rough-cut allowance

See how kerf, edge trim and rough allowance affect a plywood cut list and the material needed for a project.

Applies to: DIY rectangular panel and board planning. United States English; user-entered dimensions and prices.

Kerf is the material removed by a cut

The planner leaves the entered saw kerf between separated parts. Measure or verify your blade's actual cut width. The sample 1/8 in value is editable and is not a recommendation for every blade.

Two 24 in lengths cannot come from a 48 in board when a positive-width separating cut is required. A layout must leave room for the cut, not just the finished lengths.

Edge trim removes an unusable margin

For a sheet, edge trim is deducted from all four sides before parts are arranged. For a board, it is deducted from both ends. A 96 × 48 in sheet with 1/4 in trim on each edge has a 95 1/2 × 47 1/2 in planning area.

When transport pre-cuts are enabled, the same edge trim is deducted from each resulting panel. A trim value represents the entire removed margin at the boundary; the planner does not subtract an extra kerf beyond it.

Rough allowance makes each blank larger

Rough allowance is added to both ends and both sides of each sheet part. For a linear board it is added to both ends only. A finished 20 × 10 in part with 1/8 in allowance per edge is planned as 20 1/4 × 10 1/4 in.

The list and labels show the finished sizes. The layout shows the rough sizes. Final sizing cuts and edge-trimming operations are not included in the displayed separating-cut count.

Edge banding needs its own design decision

This version does not automatically subtract edge-band thickness or infer veneer construction. Enter the required substrate dimensions from your own design. Keep the final assembled dimension and the panel blank dimension separate in your notes.

Set your cutting allowances →