Frequently Asked Questions

How is data stored on an RFID tag? What mechanisms are used to change data values on passive RFID tags?


Data is typically stored in user memory on a tag. This is separate from the field for the unique serial number, which can be pre-programmed or assigned by a user.

The air-interface protocol standards for passive HF and UHF tags (for example, the UHF EPC Gen 2 standard) define basic operations, including read-write, and which memory banks or blocks can be written to. Reader manufacturers often combine these low-level commands with higher-level subroutines in their software development kits, so they can be used by application developers.


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