A quick response (QR) code is a type of barcode that can be read by a digital device to provide a greater amount of information than would normally be feasible.

In other words, QR code density matters; it determines the performance of the other two variables. Higher code density requires more display real-estate to function at the desired distance.

Google’s QR code generator is limited to encoding URLs only. If you have other marketing needs such as encoding contact information, or using the QR Code as a dialer, you will have to go elsewhere.