How box dielines and fold lines work
Read cut and score lines on a regular slotted carton prototype, understand allowances, and verify SVG or PDF print scale before assembly.
Have your measurements ready? Put the method to work.
Box Dieline GeneratorA dieline describes a flat construction
A dieline maps a three-dimensional carton to a flat blank. Cut lines define the edges and slots; score lines mark where the board folds. A glue tab joins the side seam. Cutting a score line would separate panels that should remain connected.
A regular slotted carton uses four side panels and top and bottom flaps. In the basic construction, flap depth relates to half the carton width so that the outer flaps meet near the center. PackCalcs supports this construction as a dimensioned prototype, not every style in the FEFCO library.
Know what the allowance model does
Enter internal length, width, and height in millimeters. This generator adds one board thickness to each score-to-score panel span and to the body height. Default flap depth is half the adjusted width; the optional extra flap allowance extends it. A configurable slot separates neighboring flaps.
These explicit allowances make the model reproducible, but they are not a universal converting specification. Board flute, score compression, folding direction, joint construction, machinery, and manufacturing tolerances affect a production blank. A converter must approve those details.
Worked example: a 300 × 200 × 150 mm carton
With 3 mm board, the alternating panel spans are 303, 203, 303, and 203 mm. Their sum is 1,012 mm. Add a 30 mm glue tab to obtain a blank width of 1,042 mm.
Body height is 153 mm. With no extra flap allowance, each flap is 203 ÷ 2 = 101.5 mm deep, so blank height is 153 + 2 × 101.5 = 356 mm. The enclosing blank rectangle is 0.370952 m²; that is not a net material area after slots and edge cuts.
Print at verified scale
SVG stores explicit millimeter dimensions. The PDF export uses physical page dimensions; tiled A4 output divides a large design across pages with overlap. A screen preview can be zoomed freely without changing export dimensions.
Print at actual size or 100%, turn off fit-to-page, and measure the 50 mm calibration line with a reliable ruler. Check both horizontal and vertical dimensions of the blank after assembling tiles. Printer margins, driver scaling, and page handling can still affect the physical output even when the digital geometry is correct.
Assemble and inspect a sample
Cut the solid outline and slots. Pre-fold the dashed scores, join the glue tab inside the opposite side panel, then close the short flaps before the long flaps. Use suitable tools and material for the prototype, and check the finished internal dimensions with the intended contents.
Inspect whether the flaps meet as intended, the seam stays square, and the box closes without distortion. Send the prototype and requirements to the manufacturer for production engineering; do not present this generated file as an approved industrial die or a structural packaging test.
Technical references
Service rules and equipment can change. Verify the specifications for your shipment.