Convert JWK

Convert JSON Web Key parameters between JWK and common key encodings.

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ToolJWK Converter
Input
Output
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Preview

How it works

JWK members describe a cryptographic key using base64url-encoded parameters such as an RSA modulus and exponent or elliptic-curve coordinates. Conversion maps those parameters to a selected PEM, DER, or JWK representation without changing key material.

  • Base64url and registered member names keep JOSE keys portable.

Worked example

Inspect JWK
Display information about a JSON Web Key
Input
											{"kty":"EC","crv":"P-256","x":"f83OJ3D2xF1Bg8vub9tLe1gHMzV76e8Tus9uPHvRVEU","y":"x_FEzRu9m36HLN_tue659LNpXW6pCyStikYjKIWI5a0"}
Output
												=== JWK Key Information ===
Key Type (kty): EC
Type: Elliptic Curve Key
Curve: P-256
Contains: Public key only

When to use this

JWKS endpoints, OAuth key imports, and browser API workflows convert JWKs.

Edge cases

  • Base64url omits padding unlike ordinary Base64.
  • A public JWK must not be treated as a private key.
  • Curve name and coordinate lengths must agree.

References