There are many different printers that are compatible with Shippo.
You can either use a standard inkjet printer, which prints on 8.5x11 inch pages or you can use a thermal label printer (e.g. Dymo 4XL), which prints on 4x6 inch adhesive paper. If you plan to ship quite a significant volume on a regular basis, then we recommend investing in a thermal label printer as it will increase the speed of your shipping process significantly.
Insider tip: We have a Dymo 4XL in our office, but many of our customers also use Zebra or Brother models if you'd like a comparison.
The labels printed via standard inkjet printer will be horizontal, letter (PDF) format on 8.5x11 inch paper. On this paper you can print a maximum of two labels per page (each label takes up half a page). The labels printed via thermal label printer will be vertical and 4x6 inch.
Please ensure that you've selected the correct default label type depending on your printer by clicking "Settings" on the left toolbar of your Shippo dashboard, then click "Labels"
We recommend testing these sizes and see actual labels by using test mode for a particular carrier.