Binary inspection
ASN.1 Lens
Inspect BER and DER structures directly in the browser with format detection, a readable tree view, and zero server round-trips.
Decode ASN.1 payloads without leaving the page
Paste a payload, load a local file, or start from the sample. Everything runs locally in your browser.
- 1Paste PEM, Base64, or Hex input, or load a local file.
- 2The parser detects the format, normalizes the bytes, and decodes the BER or DER structure.
- 3Review the resulting tree with offsets, lengths, and content previews.
SEQUENCEbytes 0-12 | header 2(2 elem)
UTF8Stringbytes 2-9 | header 2Zento
INTEGERbytes 9-12 | header 21
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