A QR code should be at least 2 x 2 cm (0.8 x 0.8 inches) for reliable scanning. A good rule of thumb is to make it roughly 10% of the surface area where it's placed. For product packaging, aim for at least 1 x 1 inch. For posters, signage, or in-store displays scanned from a distance, go larger. Digiphy lets you download QR codes in high-resolution SVG and PNG formats optimized for print at any size.
