GS1-128 Quiet Zones on Logistic Labels
For the GS1 logistic-label context cited here, the barcode must have clear quiet zones at least 10 X-dimensions wide on each side. That 10X value is scoped to this application and must not be copied to every barcode symbology.
Use the numbers from your actual job
The guide explains the decision; the linked calculator gives you the value for your own file or production assumptions.
Quiet zone means intentionally empty barcode space
The quiet zone is a clear margin that helps the scanner distinguish the start and end of the symbol. It should not contain borders, text or graphics that invade the required clear width.
The width scales with X-dimension
The cited GS1 Logistic Label Guideline specifies at least 10 X-dimensions at each side for barcodes in its scope. If X changes, the absolute clear-space requirement changes with it.
Do not generalize 10X to 2D symbols
GS1 specifications contain different requirements by symbol and application. For example, 2D symbols have their own quiet-zone rules, so always identify the actual symbol and scanning environment before using a calculator.
Practical answer
For the GS1 logistic-label context cited here, the barcode must have clear quiet zones at least 10 X-dimensions wide on each side. That 10X value is scoped to this application and must not be copied to every barcode symbology.
When the decision affects a paid print run, book upload, client order or expensive material, keep the calculation with the job notes and verify any external specification again immediately before production.