Convert a .cer certificate - PEM text or binary DER - into a Base64 PEM (.pem) certificate file. Everything runs in your browser.
A .cer file may be Base64 PEM or binary DER. PEM is the Base64 text format used by most Linux servers and web applications. This tool detects the input format automatically and outputs a valid .pem certificate - the browser equivalent of openssl x509 -inform DER -in cert.cer -out cert.pem for binary input.
Convert and package keys for SSH, TLS, and keystore workflows.