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NFC tag type specification

Doing a research on NFC tag types, I have stumbled upon few questions.

During a time of this question I have read many articles about NFC tag types, and every article provides different type of information, rarely do they provide the same.

For example, in one article describing NFC tag 1, the information says that its capacity is up to 96 bytes, but the other shows that it is up to 454 bytes. Same is with read/write speeds.

So my question is, does anyone have reliable information about all 5 NFC tag types, that I could read and be sure that it is correct?

Solution

  • There is no single correct answer to the question "What exact amount of memory can be stored on a Type X Tag?" The five different tag types (tag platforms) specified by the NFC Forum characterize different tag technologies (specifically different communication protocols and memory layout) and originate in the different RFID tag technologies that were "merged" into NFC:

    • the Type 1 Tag platform is based on Topaz tags (formerly Innovision, now Broadcom?),
    • the Type 2 Tag Platform is based on MIFARE Ultralight (NXP), but there is also Type 2 tag chips from various other manufacturers (e.g. Infineon),
    • the Type 3 Tag Platform is based on FeliCa (Sony),
    • the Type 4 Tag Platform originates in MIFARE DESFire (NXP), but there is various other manufacturers too,
    • the Type 5 Tag Platform is based on ISO/IEC 15693 tags (various manufacturers have compatible tags).

    Chip manufacturers have various tag products with different storage capacity that comply to those tag platform specifications. E.g. there are Type 1 tags with 120 bytes total memory (<= 92 usable for NDEF data) and also with 512 bytes total memory (<= 454 usable for NDEF data).

    Since the NFC Forum tag specifications define the the memory layout, there are typically lower and upper bounds to the storage capacity of NFC tags:

    • Type 1: max. 2048 bytes of physical memory are addressable (only parts of that can be freely used for the NDEF message)
    • Type 2: max. 2040 bytes of user data memory are addressable (or was there an extension in a newer version?)
    • Type 3: max. 1024 minus 16 bytes of user data memory are addressable
    • Type 4: max. 64 KB of user data memory in one NDEF file are addressable

    The most reliably source for information regarding the theoretical limits of the NFC tag types are the NFC Forum specifications themselves. You can obtain them from NFC Forum. Regarding actual implementations, there really is no single source. YOu will have to dig into manufacturers' datasheets.