What this tool is good for
This page signs UTF-8 text with an Ed25519 private key and verifies Base64 signatures with the matching public key. It is useful when debugging message signing flows, APIs, and application protocols.
All signing and verification is handled locally in the browser, so sensitive keys do not need to leave your machine.
Ed25519 here refers to the Ed25519 signature scheme standardized in RFC 8032, with raw message signing and verification rather than certificate packaging.
Key requirements
- Signing accepts a Base64 private key that decodes to 32 bytes or 64 bytes.
- Verification requires a Base64 public key that decodes to exactly 32 bytes.
- The signature field expects a Base64-encoded Ed25519 signature.
Typical workflow
- Paste the message and private key to generate a signature.
- Paste the same message, the public key, and the signature into the verify panel.
- If the signature was produced by the matching private key and the message is unchanged, verification succeeds.
FAQ
What does Ed25519 signing prove?
An Ed25519 signature proves that a message was signed with the matching private key and that the signed message has not changed since the signature was created.
Do I need the private key to verify an Ed25519 signature?
No. Verification uses the public key, original message, and signature. The private key is only needed when creating a new signature and should not be shared.
Why does Ed25519 signature verification fail?
Verification fails when the message, public key, or signature does not match exactly. Extra spaces, changed line endings, different encodings, or a mismatched key pair can all invalidate the result.
Related tools
- Ed25519 Key Pair Generator：Generate random Ed25519 public and private keys