Sample PEM certificate and CSR for testing — free, CC0

PEM is the base64 armour around a certificate — the form that gets pasted into configuration files, environment variables and deployment scripts, wrapped in BEGIN and END lines.

pem/self-signed-ed25519-cert.pem is a self-signed Ed25519 certificate for the reserved name fixture.example, valid from 2020 to 2120 with a fixed serial. Ed25519 is the modern choice and is still refused by older libraries, which makes it useful for finding out what your stack actually supports.

The key is derived from a published seed, so anyone can rebuild the certificate and verify it is what it claims to be. No private key is published here — a validator refuses any fixture containing one — and the certificate names only a reserved example domain, so it can never be mistaken for a credential belonging to a real host.

Use it to test certificate parsing, trust-store loading, expiry handling and error messages for an untrusted chain. Related format: DER, the same certificate in binary.

curl -O https://loremfile.dev/pem/self-signed-ed25519-cert.pem

<a href="https://loremfile.dev/pem/self-signed-ed25519-cert.pem">download</a>