Ed25519 Key Generator — Sign & Verify
Free online Ed25519 key pair generator with message signing and signature verification. Uses the Web Crypto API. No sign-up, runs in your browser.
What Is Ed25519?
Ed25519 is a modern elliptic-curve digital signature algorithm that provides high security with short keys and fast performance. It is based on the Edwards-curve Digital Signature Algorithm (EdDSA) using Curve25519. Ed25519 is used in SSH, TLS, cryptocurrency wallets, and many authentication protocols. A 32-byte public key and 64-byte signature provide 128-bit security.
How to Use This Ed25519 Key Generator
- Click Generate Ed25519 Key Pair to create a new public/private key pair.
- Copy the public key (SPKI PEM) or the raw Base64 format for use in your application.
- Keep the private key (PKCS8 PEM) secure — never share it.
- Use the Sign section to sign messages with the generated private key.
- Use the Verify section to check a signature against the public key.
Common Use Cases
- SSH Key Generation — Generate Ed25519 keys for SSH authentication, the recommended algorithm for modern OpenSSH.
- Digital Signature Testing — Test signing and verification workflows for APIs, JWTs, or blockchain applications.
- Learning Cryptography — Understand how public-key cryptography works by experimenting with key generation, signing, and verification.
FAQ
Is Ed25519 better than RSA?
Ed25519 offers equivalent or better security with much smaller key sizes (32 bytes vs 256+ bytes for RSA-2048) and significantly faster operations. It is the recommended algorithm for new SSH keys.
Which browsers support Ed25519 in Web Crypto?
As of 2025 Chrome, Edge, Firefox, and Safari all support Ed25519 in the Web Crypto API. Older browsers may not.
Is my private key sent anywhere?
No. Key generation uses your browser Web Crypto API. No data leaves your device.