TLV Decoder

The TLV Decoder processes hex-encoded data and outputs a structured TLV tree. It supports multi-byte tags, long-form lengths, and nested (constructed) tags, enabling researchers to explore complex binary protocols. Conceptually, the tool reads bytes, determines tag boundaries, decodes length fields, and extracts the value segment, repeating recursively for nested structures. The resulting representation shows a clear path from the root to each leaf, with offsets and hex/ASCII value representations where meaningful. This helps users audit data flows, verify protocol conformance, and identify malformed or unexpected TLV sequences. The tool emphasizes structural accuracy and error transparency, rather than interpreting the semantics of specific tags. Practical use cases include EMV transaction data analysis, smart card debugging, NFC payload inspection, and security testing of binary communication protocols. Its uniqueness lies in precise BER-TLV parsing, robust error reporting for truncated or malformed TLV, and the ability to export or view the entire TLV tree in a consistent, machine-readable format. The core value is accelerated protocol reverse engineering and faster fault isolation in firmware or middleware that relies on TLV-encoded data. Use cases range from validating card payment data to evaluating binary protocol compliance in embedded devices.