Common failure points
The browser adds margins or headers around the downloaded label.
Fit to page changes the label's physical dimensions.
A crop removes small text or the edge of a code.
The wrong printer preset is reused from a previous job.
From source PDF to a print-ready label
Download, do not screenshot
The marketplace PDF is the best-quality source available.
Inspect the entire label
Make sure the address, routing marks and codes remain inside the crop.
Use the correct media preset
Print the exported PDF at Actual size and verify the preview before confirming.
Questions before you print
Can I use a 4×6 thermal printer for every envelope label?
Not necessarily. Follow the current marketplace requirements for that service and packaging type.
Why does the barcode look blurry?
Screenshots, browser zoom and image resampling can soften bars. Start from the PDF and avoid unnecessary conversions.
Does LabelCheckup buy or create postage?
No. It only checks and reformats a PDF you already have.