One can’t determine an accurate minimum printing size for a static QR Code because static QR Codes can contain a variable amount of data.
On the other hand, a dynamic QR Code should be printed at least at 2 centimeters (0.8 inches) square to maintain reasonable scannability and sanctity.
Calculate the required size based on the print resolution
Follow this formula to calculate a QR Code's size in inches if you need to print a QR Code with, say 1024 pixels:
Size (in inches) = Number of Pixels / Print Resolution (in pixels per inch)
For example, if your QR Code has 1024 pixels and you are printing at a resolution of 300 pixels per inch, the required printing size would be:
Size = 1024 / 300 = 3.413 inches
Other important factors
Arriving at a QR Code's required size also depends on factors such as:
the data it contains,
QR Code reader tool,
lighting,
distance from the scanning device,
print quality, and
scanning device.
It's also crucial to ensure proper contrast, correct printing techniques, and suitable background colors so it can be scanned from a distance, even by devices with low-resolution cameras.
It's recommended to test the printed QR Code at various sizes and distances to verify its scannability to ensure the best results.
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