ISO vs US Paper Sizes
Understand which size family you are choosing before exporting or printing.
ISO A series
ISO 216 lists trimmed A series sizes in millimeters. A4 is 210 × 297 mm; each neighboring A size is approximately half or double the sheet area.
North American formats
Letter measures 8.5 × 11 inches, and Legal measures 8.5 × 14 inches. They differ from A4, so choose the actual printer paper size when preparing margins.
Avoid unintended scaling
Before printing, check the document size, printer tray, and “fit to page” setting. If the source and destination sizes differ, the print dialog may scale or crop the page.