ISO 7816-4 CLA Decoder
Decode the ISO/IEC 7816-4 CLA (class) byte: interindustry vs proprietary classification, secure-messaging bits, command-chaining indicator, and logical-channel number.
Input
Decoded
Enter a CLA byte.
All decoding runs locally.
About CLA
The CLA byte sits at the start of every APDU (CLA INS P1 P2 [Lc] [data] [Le]). Its bit-fields tell the card whether the command is interindustry or proprietary, whether secure messaging is wrapping the body, whether command chaining is in progress, and which logical channel the command targets.