Real DER/ASN.1 parsing — browser-only

X.509 Certificate Viewer

Drop or upload any X.509 certificate file — PEM, CRT, CER, or raw DER — to decode all fields: subject, issuer, validity, public key, extensions, and real cryptographic fingerprints.

PEMDERCRTCERSHA-1 fpSHA-256 fpExtensions

Real fingerprints

SHA-1 and SHA-256 fingerprints are computed with crypto.subtle.digest on the raw DER — identical to OpenSSL output.

File Input

Drop a certificate file.

Drag & drop your certificate here

or click to browse

Supported: .pem · .crt · .cer · .der

Related Tools

CSR Decoder — Certificate Signing Request Parser

Decode and inspect PEM-encoded Certificate Signing Requests to view subject details and public key info.

PEM / Certificate Viewer — Inspect SSL Certs

Inspect PEM-encoded certificates, public keys, and CSRs — view type, subject, issuer, validity, and fingerprint.