ASN.1 パーサー

ASN.1 パーサー

Decode and inspect ASN.1 (Abstract Syntax Notation One) encoded data used in X.509 certificates, PKCS structures, and cryptographic protocols. Paste hex, base64, or PEM-encoded data and instantly see the full parsed structure.

使い方

1. Paste your ASN.1 data in hex, base64, or PEM format into the input field.

2. The parser auto-detects the input format and decodes the TLV (Tag-Length-Value) structure.

3. View the parsed output showing tag types, lengths, and values with nested indentation.

4. OIDs are displayed in both numeric and human-readable named format.

5. Export the parsed structure as JSON or copy the output to clipboard.

特徴

• DER/BER Decoding – Parse binary ASN.1 structures with full Tag-Length-Value breakdown
• 複数の入力形式 – Accept hex strings, base64, or PEM-encoded data with auto-detection
• OID Resolution – Map Object Identifiers to human-readable names (X.509, PKCS, hash algorithms)
• Nested Structure – Indented display for SEQUENCE, SET, and other constructed types
• All Universal Tags – SEQUENCE, INTEGER, OCTET STRING, BIT STRING, BOOLEAN, NULL, OID, UTF8String, PrintableString, and more
• JSONエクスポート – Export the parsed tree structure as JSON for further processing
• クライアントサイドのみ – All parsing happens in your browser; no data leaves your machine