How this works. The symbol is built here in your browser to ISO/IEC 18004 — segment encoding, Reed-Solomon error correction, and mask selection by penalty score — then drawn through one geometry pass that feeds both the on-screen canvas and the vector export, so what you see is what you ship. Nothing is uploaded: your link and your logo never leave this page. Test decode runs an actual image-based decoder over the rendered pixels, which is the only honest way to know a styled code still scans.