APDU Script Validator
Validate a multi-line APDU script line-by-line. Each APDU is classified into ISO 7816-4 case 1 / 2 / 3 / 4 (short or extended) and checked for shape consistency. Validation only — no execution against any card.
Script
Validation
Paste an APDU script.
All decoding runs locally.
About APDU validation
An APDU has a fixed 4-byte header (CLA INS P1 P2). The body shape distinguishes case 1 (none), 2 (Le only), 3 (Lc + data), 4 (Lc + data + Le). Extended length is signalled by Lc starting with 0x00. This validator is shape-only — it never executes APDUs.
Spec
ISO/IEC 7816-4 §5.3 (APDU structure).