How to use PEM / JWK
- 1. Paste PEM or JWK. PUBLIC KEY / PRIVATE KEY blocks, or a JWK object.
- 2. Convert. PEM → JWK or JWK → PEM.
- 3. Optional SSH line. RSA public JWK only.
- 4. Copy locally. Nothing is uploaded.
About this tool
JWTs, WebAuthn, and SSH disagree on key packaging. This tool converts SPKI/PKCS8 PEM to JWK and can emit an ssh-rsa line from an RSA public JWK so the same material can be pasted into authorized_keys or a JOSE header.
Supported
RSA and EC keys that Web Crypto can import as SPKI/PKCS8 or JWK.
Not supported
OpenSSH private keys, PKCS#1 RSA PRIVATE KEY without conversion, and X.509 certificates — use a future PKI tool.
Code examples
JWK
{ "kty": "EC", "crv": "P-256", "x": "…", "y": "…" }