A margin that looks safe on screen can still fall in the trim variance zone or get eaten by folding or binding. Safe area is not a guess; it is a defined distance from trim or fold.
Trim variance
Cutters do not hit the same line every time. A 1/16" variance is normal. Content placed within that zone can be clipped. Keep critical content at least 1/8" inside trim; more for large-format or guillotine-cut work.
Folds and binding
Folded and bound pieces lose margin to the fold and to the binding edge. Content too close to the fold can be hard to read or can crack; content too close to the bind can disappear into the gutter. Allow extra margin for fold and bind.
Practical safe area
• Sheet work: at least 1/8" (0.125") from trim for critical text and logos.
• Folded work: keep important content away from the fold line (typically 1/8"–1/4").
• Bound work: allow gutter margin so type does not sit in the binding.
Common mistake
Using a 1/8" margin and placing a key line or rule exactly on it. Trim variance can put the rule on the edge or cut it. Keep critical elements clearly inside the safe zone.