The size and structure of the iClass card memory varies. It is divided into card size and application allocation.
2K / 2 Application
16K / 2 Application
16K / 16 Application
32K (16K / 2 + 16K / 1)
32K (16K / 16 + 16K / 1)
For example, block index can be seen as below in case of 2K non-configured card, 2K configured card and 2K programmed card.
2K/2 Card = 2 * 1024 bits = 256 bytes
Recommended template size is minimum 300 bytes so you can't write template data in 2K/2 card due to size but you can use as Bypass card when you want to use it as a smart card.
1 Block = 8 bytes
1 Page = 2 Application
The application consists of blocks. The number of blocks differs depending on the application size.