Put a logo, QA stamp, or brand mark on every label your system prints, without touching the ZPL that generates them. Upload the mark, drag it into place, and take the API call with you.
Output carries a light watermark. Sign in and create a free API key; then every run here is watermark-free (500 credits a month, no card).
Drag the mark ·
at (0, 0) dots
The stamper adds an image to labels you did not design: the carrier label your shipping API returns, a supplier's product label, any ZPL you receive rather than write. Upload the logo or mark, drag it to the spot on the label, and the tool merges a dithered ^GFA of it into the ZPL at that position.
The output is the stamped ZPL plus the API call that does the same thing to every label in production, so a return-address block, a franking mark or a compliance logo can be applied at print time without touching the source system.
The mark is placed in printer dots at the density you choose and previewed on the actual label, so you can see it clearing the barcodes and quiet zones before it goes near a scanner.
Your data: Your logo and ZPL are processed in memory and discarded when the response is sent; nothing is stored, logged or read by a person. Anonymous runs carry a small stripyhorse.io logo in the corner; sign in for clean output. Details in the privacy policy.
Only if you put it there. The preview shows the real label; keep the mark out of the quiet zones and run the result through Preflight to be sure the codes still decode.
A black-and-white PNG at or above the printer's resolution. Colour and grey are dithered, which reads as speckle at small sizes.
Copy the API call the tool shows: POST /v1/stamp with your ZPL, the image and the position. The SDKs expose it as one method.
The same engine is behind the API and the guides; every tool here is also an API call.