When it comes to NFC Tags, size does matter. In fact, the larger the Tag’s antenna, the greater its reading range. For this reason, if you have no space problems, we generally recommend Tags with a fairly large antenna, especially if you plan to place the Tag behind a panel or glass.
In relation to the reading distance, please note that, for the same size, the On-metal Tags have a lower range.
In general, we advise against choosing Tag with an antenna less than 12 mm (side or diameter), because is hard to detect, especially with a normal smartphone.