DESFire Access-Rights Decoder
Decode the 16-bit DESFire access-rights word into the four key references it controls: Read, Write, Read+Write, and ChangeAccessRights. Reference content based on public ISO/IEC 14443-4 framing and NXP application notes.
Input
Decoded
Paste hex to decode.
All decoding runs locally.
What the four nibbles mean
DESFire access-rights are encoded as a 16-bit value, four 4-bit fields: b15..b12 Read, b11..b8 Write, b7..b4 Read+Write, b3..b0 ChangeAccessRights. Each field is a key number 0…13, or 0xE for free access (no authentication required), or 0xF for “always denied”. So 0x1230 means: read with key 1, write with key 2, read+write with key 3, and change-rights with key 0.