Modern signatures
Ed25519 is an EdDSA signature scheme on Curve25519. It is fast, uses small 32-byte keys and 64-byte signatures, and avoids pitfalls of older schemes, such as needing good randomness every time it signs. OpenSSH, Tor onion services, minisign and JWTs with the EdDSA algorithm all use it.
This page creates the pair with your browser’s Web Crypto API. PEM output works with OpenSSL 1.1.1 and later, JWK suits JOSE libraries, and raw hex gives the 32-byte public key and private seed directly.
Need an SSH key instead?
SSH uses its own file format. The SSH key generator creates Ed25519 keys in OpenSSH format, ready for ~/.ssh and authorized_keys.
Frequently asked questions
Which browsers support Ed25519 in Web Crypto?
Current versions of Chrome, Edge, Firefox and Safari. If your browser is older, the page will tell you, and the openssl command on this page works on any system.
Is Ed25519 safe against quantum computers?
No. Like RSA and ECDSA, it would be broken by a large quantum computer. Post-quantum signature schemes are being standardized, but Ed25519 remains a strong choice against today’s attackers.