Purpose-Built
A private ASN.1 BER/DER explorer for tag-length-value trees, OIDs, X.509 certificates, CSRs, PKCS structures, extension bytes, hex ranges, and schema-assisted decoding.
One-time iPhone and iPad app
Derweave
DER trees and certificates
Core Features
- Decode definite BER and canonical DER TLV trees
- Map common OIDs and X.509 fields
- Inspect certificates, CSRs, and PKCS containers
- Link every node to exact source-byte ranges
- Export annotated hex and structural JSON
Private by Design
No account, subscription, ads, tracking, third-party analytics, or developer-operated backend. Core features work offline, and your work stays on device unless you deliberately share or export it.
Use It Responsibly
Inspection and learning aid. Trust, revocation, policy, identity, and cryptographic validity require an appropriate validation environment.