Crypto & Hash

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.

Free to use No sign-up Runs in your browser

Tool workspace

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

  1. 1Click Generate Ed25519 Key Pair to create a new public/private key pair.
  2. 2Copy the public key (SPKI PEM) or the raw Base64 format for use in your application.
  3. 3Keep the private key (PKCS8 PEM) secure — never share it.
  4. 4Use the Sign section to sign messages with the generated private key.
  5. 5Use 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.

Frequently asked questions

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.