What is a 100×150 mm thermal label?
The 100x150 thermal label (100 × 150 mm) is the most common shipping label size on roll thermal barcode printers such as Xprinter, Zebra and TSC. It is 10 cm wide and 15 cm high; the barcode, address block and tracking number fit comfortably in this area. Because the roll width is 100 mm, the paper width in the printer settings must also be set to 100 mm.
This size is the target that labels produced for A4 by marketplaces are cropped and moved into. When cropped correctly, the barcode prints at its real size and a handheld scanner or phone camera reads the label on the first try.
Why a thermal label instead of A4?
- Speed: A roll thermal printer prints without waiting per page.
- Cost: There is no toner or cartridge expense; only the label roll runs out.
- Clarity: The barcode is printed directly on thermal paper; even 203 dpi is enough for a shipping barcode.
- Adhesive: The label goes straight onto the package; no cutting or taping.
- No scaling: When printed on a 100×150 mm canvas, the printer does not try to shrink the content.
Moving from an A4 label to 100x150 mm
Marketplace labels are produced as A4, so they cannot be sent straight to a thermal printer. KargoLabel crops the label area in the A4 PDF and moves it onto a 100×150 mm canvas. Because the PDF is not converted back to an image, the barcode and text quality are preserved as much as possible.
When you print, use the "actual size" option in the printer's own driver. If you print from a browser, set the margins to zero and turn off scaling.
Correct print settings
- Paper size: 100 × 150 mm; roll width 100 mm.
- Scale: 100% / actual size; "fit to page" off.
- Orientation: portrait.
- Density/darkness: the middle value the manufacturer recommends; too low a density fades the barcode.
- On the first run print a single label; scan the barcode with the reader, then print in bulk.
Storing the label and readability
Thermal paper fades when it is exposed to heat and sunlight for a long time. Do not leave printed labels in places that get direct sun or on hot surfaces; keep them in roll form in a cool, dry place until the day you use them.
Sticking clear tape over the barcode can also hurt readability: the tape reflects light and creates glare that the reader cannot see through. When you stick the label on the package, take care not to cover the barcode.
The difference between 203 dpi and 300 dpi
Thermal barcode printers are mostly made at 203 dpi resolution; standard shipping barcodes read comfortably at this resolution. 300 dpi models give a cleaner result on thin lines and small type; they offer an advantage if the label has a QR code, a long tracking number or small text.
Print darkness also affects readability: with too light a print the barcode lines stay faint, and with too dark a print the lines run into each other. Starting with the density the manufacturer recommends and scanning the first label with the reader is the safest route.
- 203 dpi is usually enough for a standard shipping barcode.
- If small type and QR codes are dense, 300 dpi gives a cleaner output.
- Calibrate the density setting with a test print.
Does a 100x150 thermal label work on every printer?
It works with most thermal barcode printers with a 100 mm roll width; on models such as Xprinter, Zebra and TSC this size is available in the standard settings. It can also be printed on a laser printer with label paper loaded.
Should I choose 80x120 mm or 100x150 mm?
On small packages 80×120 mm is enough and takes up less space. If the recipient's address is long, the courier company wants extra space or the barcode reader struggles, 100×150 mm is the safer choice.
Is a 203 dpi printer enough for a shipping barcode?
Yes. Standard shipping barcodes read reliably at 203 dpi. Only if small type or small QR codes are dense does a 300 dpi model give a cleaner result.