Printing marketplace labels on 4x6 and 3x5 thermal stock

Almost every Indian marketplace hands you shipping labels as A4 PDFs. That made sense when sellers printed on office laser printers and cut labels out with scissors. Today most sellers who ship more than a handful of parcels a day use a thermal printer loaded with 4x6 or 3x5 inch labels. Thermal printing is faster, needs no ink and gives you a sticker that goes straight on the packet.

The catch is that an A4 page does not fit on a 4x6 label. If you print the A4 file as it is, the printer shrinks the whole page, including the empty space and the fine print, and your barcode ends up too small to scan. The fix is to cut each label out of its A4 page first, then place it on a page that matches your roll.

Choosing between 4x6 and 3x5

4x6 inch (about 100 × 150 mm) is the safe default. It holds every marketplace label at a comfortable size and leaves room for a caption. 3x5 inch (about 75 × 125 mm) is cheaper per label and suits smaller packets, but some layouts have to be shrunk more to fit.

A rough guide based on how each marketplace lays out its label:

• Flipkart: the cropped label fits 4x6 at roughly 108% and 3x5 at almost exactly 1:1. Either works well.
• Amazon: the label is cut to its own 4x6 picture and printed at full size. 4x6 is the natural choice.
• Meesho: the crop keeps the label plus a shrunk tax invoice band, so it is taller than a bare label. It is scaled down to fit 4x6; 3x5 works but is tighter.
• Snapdeal and AJIO: 4x6 is the comfortable fit.

How scaling works

CropMyLabel crops each label to its content and then scales it to fill your chosen page as fully as possible without distorting it. If a label fits the stock better turned sideways, it is rotated automatically. You can also pick "Crop" as the page size, which gives you a page exactly the size of the cut label with no scaling at all; this is useful if your printer driver does its own fitting or you print on plain paper.

Because the label is kept as vector content rather than turned into an image, scaling up or down does not blur it. Lines and barcodes are redrawn sharply at whatever size the printer needs.

Why the caption is sized after scaling

Each label can carry a small caption table with the SKU, size, quantity and crop time, so whoever packs the parcel knows what goes inside without opening the invoice. If that caption were added to the A4 page before scaling, it would shrink along with a Meesho label and become hard to read.

Instead, the caption is drawn at the final print size, after the label has been scaled onto the 4x6 or 3x5 page. The text height you see on screen is the text height you get on the sticker. If your packers still find it small, raise the caption size; it goes from 60% to 220%. Larger captions take space from the label, so increase it in steps and check the preview.

A quick checklist before a big batch

Before you print two hundred labels, print two and check them properly.

• Page size in CropMyLabel matches the roll in the printer.
• The print dialog is set to actual size or 100%, not "fit to page".
• Margins are set to none.
• The test label scans with a phone barcode app from a normal distance.
• The caption is readable at arm’s length.