PEM and DER Converter

Convert a certificate between PEM and DER (binary), see it as base64 or hex, and get the openssl commands for PKCS#12 (PFX), PKCS#7 and key conversions. Runs in your browser.

Paste PEM, or choose a .der / .cer / .crt file

Decoded in your browser: nothing you paste is sent to us.

Other conversions (run these locally)

# PEM certificate + key -> PKCS#12 (.pfx) for IIS, Azure, Java
openssl pkcs12 -export -in cert.pem -inkey key.pem -certfile chain.pem -out site.pfx
# PKCS#12 -> PEM
openssl pkcs12 -in site.pfx -out all.pem -nodes
# PKCS#7 (.p7b) -> PEM
openssl pkcs7 -print_certs -in chain.p7b -out chain.pem
# PKCS#1 RSA key -> PKCS#8
openssl pkcs8 -topk8 -nocrypt -in rsa.key -out key.pem

Check a live site

The SSL Certificate Checker reads the certificate your server actually sends, its chain, revocation, CAA and renewal health.

Open the SSL Certificate Checker