How to use RSA / ECDSA
- 1. Generate a key pair. RSA-PSS 2048 or ECDSA P-256.
- 2. Copy PEM or JWK. Both stay in memory until you leave.
- 3. Sign a message. Signature is hex.
- 4. Verify. Uses the matching public JWK.
About this tool
Asymmetric keys are easier to inspect when you can mint a throwaway pair and sign a string without OpenSSL. This tool uses Web Crypto in the browser: RSA-PSS with SHA-256, or ECDSA on P-256.
Algorithms
RSA-PSS salt length 32. ECDSA hash SHA-256. There is no RSA-PKCS1v1.5 here.
Never for production secrets
A tab is not an HSM. Generate real keys in your own pipeline.
Code examples
JWK kty
{ "kty": "RSA" }