A die line is a template drawn as a thin line, usually in a bright spot color like red or magenta, that shows the exact shape a cutting die will make. It is used for anything that is not a plain rectangle: shaped stickers and labels, pocket folders, boxes, door hangers and packaging. Fold and score lines are often marked too.
The die line has to stay separate from the printed art so the cutter can read it and the press does not print it. Building artwork around the printer's real template, not a guessed shape, is what keeps the cut from slicing through a logo or leaving a gap at the edge.
Imagine a candle maker called Wick & Ember ordering round labels with a scalloped edge. The printer supplies a die line; the designer places the art inside it with bleed outside, and the labels come back cut cleanly around every scallop.
In aiKit, Printer's Helper asks before building a special shape. You can use your printer's saved template, upload your own die line, or use a standard shape that is marked as assumed. Die lines are made as their own 1 pt file, and custom die cuts stay approximate until your printer confirms them.
Related terms
See it in practice
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Send print proofs with cut and safe lines. Customers pin comments and approve by typed name from a phone, no account. Free to start with aiKit.
Use caseAI quotes for sign shops: from a customer's email to an accepted quote
Paste a sign request and get a one-page quote priced from your own prices, with options and add-ons, then a live page your customer accepts. Free to start.