Generate Ed25519 key

Generate an Ed25519 signing key pair from a 32-byte seed.

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ToolEd25519 Key Generator
Input
Output
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How it works

Ed25519 expands a 32-byte private seed with SHA-512, clamps part of the digest into a scalar, multiplies the Edwards base point, and encodes a 32-byte public key. Signatures use deterministic nonce derivation from the expanded secret and message.

  • Fixed curve and key sizes make Ed25519 compact and interoperable.

Worked example

Generate Ed25519 Key Pair
Generate an Ed25519 signing key pair in hex format
Input
											hex
Output
												=== Ed25519 Private Key (Seed) ===
80a1c6a4aa9cc8f280c1b9b9b3d0ae0b73e62292ee16043c225638fe7760e9a0

=== Ed25519 Public Key ===
636fa604fe9ed7ffcd7685f85cf11d8296ddf5df0a7dffd56584e35aff598550

Format: hex
Private key: 32 bytes (256 bits)
Public key: 32 bytes (256 bits)

When to use this

SSH identities, software release signing, and deterministic test fixtures use Ed25519.

Edge cases

  • A seed is not the same byte sequence as a serialized private key.
  • Changing one message byte changes the signature.
  • Ed25519 signatures are not interchangeable with ECDSA signatures.

References