How can I read the UID of my NFC tag?

The NFC chip UID (unique ID) data is stored in a separate part of the chip memory to that where you would store the URL (or other NDEF data). Therefore, you need to use an NFC App.

We suggest either NFC Tools or NXP's TagWriter for Android and NFC Tools on the iPhone. After opening the App, you can scan the tags to see the entire memory structure including the UID.

It's possible to also include the UID into, for example, a URL during the encoding process so that it can be visible without a specialist App. This can either be done manually (by scanning the UID and including it within the encoding data) or on the NTAG series chips, it can be dynamically added using the UID substitution feature. Note that it's not always easy to use the UID sub feature when encoding with a mobile App so we suggest testing before starting any large project !
Seritag - 13 Jan 2023