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Key Block Decoder
Decode TR-31 / ANSI X9.143 key blocks — parse version, key usage, algorithm, mode of use, exportability, optional blocks, and MAC
🔑 Input
Paste a TR-31 key block string (Version A, B, C, or D). Whitespace is ignored.
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📖 About This Tool
What is the Key Block Decoder?
The Key Block Decoder parses TR-31 key block headers to extract key usage, algorithm, mode of use, exportability, and optional block information. TR-31 is the industry standard for secure key exchange.
🛠️ How to Use
- Enter the key block header.
- Click Decode to parse the header fields.
❓ FAQ
What is a TR-31 key block?
TR-31 (ANSI X9.143) is a standard format for securely wrapping and transporting cryptographic keys between devices. The key block header contains metadata about the key type, algorithm, usage restrictions, and exportability.