RSA vs. ECDSA: Two Paths to Asymmetric Keys
Both RSA and ECDSA generate a public/private key pair for asymmetric cryptography — encrypting or signing with one key that only the matching key can decrypt or verify — but they're built on entirely different mathematical foundations. RSA's security rests on the difficulty of factoring the product of two large prime numbers; ECDSA's rests on the difficulty of the discrete logarithm problem over elliptic curves — different math, same practical goal of a problem that's easy to compute in one direction and computationally infeasible to reverse without the private key.
The practical difference that matters most day-to-day: ECDSA achieves equivalent security to RSA with dramatically smaller key sizes — a 256-bit ECDSA key offers comparable security to a 3072-bit RSA key — which translates directly into smaller certificates, faster key generation, and less data to transmit during a TLS handshake. RSA remains extremely widely supported and well-understood, which is why it's still a common default despite ECDSA's efficiency advantages.
Generated keys here follow standard formats — PKCS#8 for private keys, SPKI for public keys — the same formats real certificate authorities and TLS implementations expect, using the browser's native WebCrypto API rather than a custom implementation.