4×6 Inches vs 100×150 mm: Set the Right Label Size
LabelCropTools product documentation · Updated
Thermal labels are often described interchangeably as 4×6 inches and 100×150 mm. Their dimensions are close, but they are not identical. A small mismatch between the PDF, stock and printer driver can matter when a barcode or address sits near the edge.
Know the exact physical dimensions
One inch is 25.4 mm, so a 4×6 inch sheet measures 101.6×152.4 mm. A 100×150 mm sheet is 1.6 mm narrower and 2.4 mm shorter. PDF coordinates use 72 points per inch, so LabelCropTools's 4×6 output measures 288×432 points.
Check the specification on the roll rather than relying on a rounded product name. If the driver offers a custom paper setting, use the dimensions of the stock loaded in the printer. Do not assume that every manufacturer's preset uses the same dimensions.
Fit a complete label without distorting the barcode
A shipping label can be wider or taller than the target sheet's proportions. A proportional fit uses the same scale factor in both directions and may leave white borders. Stretching width and height separately can alter the barcode pattern.
Try Automatic rotation in the thermal converter. Landscape artwork often uses more of a portrait thermal page when turned sideways. This preserves the artwork and reduces unused space. A long address may still require a different fit from a short address.
Avoid applying scale twice
Choose the intended paper size in the tool, then confirm the driver uses the same physical stock. For a matching PDF and sheet, begin with Actual size or 100% in the viewer. Inspect the print preview before sending a job.
If you must print a 4×6 PDF onto 100×150 mm stock, check the driver's fit behaviour and printable margins using one test label. Do not assume that a rounded stock name guarantees a borderless result. Check the smallest text, the full address and the barcode quiet zones.
Separate PDF layout problems from stock calibration
If the PDF preview shows a complete label but the printer advances empty stock, investigate the roll's gap or mark settings and the manufacturer's calibration procedure. If content is missing in the PDF itself, investigate crop boundaries first.
Increasing a print margin can protect content from an unprintable edge, but it also makes the label smaller. Keep a known-good sample and change one setting at a time so you can identify what caused an improvement.
Tools for this workflow
Related reading
This guide describes the current product workflow, rather than a marketplace or printer certification. About this documentation · Report an issue · Product limitations