A cut line has width. Two finished 600 mm pieces cannot come from 1200 mm stock if a nonzero blade kerf separates them. Real cut planning must reserve material for the blade.
Count the cuts you will make
Five 400 mm pieces use 2000 mm of finished length. Five separating cuts at 3.2 mm use another 16 mm. If the last piece ends at an existing stock edge, that final cut may be unnecessary. Squaring an end may add another cut.
The kerf calculator accepts the actual cut count. The optimizers reserve kerf at their subdivisions, without requiring an imaginary cut outside the original stock edge. Sheet edge trim is a separate input.
Rotation can change the result
Rotating a rectangle may let it fit a gap. That can help for nondirectional material and cause a problem for visible grain. With rotation off, each part’s length follows the stock length.
The plywood optimizer starts with rotation off. This is a geometric convention: the tool cannot inspect the grain in the physical sheet. Identify that direction before entering the list.
Read the utilization number carefully
Material use is finished part area divided by all opened sheet area. Its complement includes blade loss, trimming, and offcuts. Some offcuts are useful later; others are too small or narrow.
A low utilization value can occur when the last sheet contains just one part. This does not prove the solution is wrong or optimal. A practical rectangle-packing heuristic may miss a better arrangement. Compare alternate stock sizes or revisit allowable orientation.
Bring the plan to your saw
Check dimensions and quantities before cutting. Decide how long cuts will divide the sheet into safely supported sections. The diagram is a dimensional plan, not an instruction to make a cut your equipment cannot support.