Bun Support

[panva]

Bun makes use of Web Cryptography API for the cryptographic operations.

JSON Web Key Type Support

	Supported	kty value
RSA	✓	RSA
Elliptic Curve	✓	EC	supported curves: P-256, P-384, P-521
Octet Key Pair	✓	OKP	supported subtypes: Ed25519
Octet sequence	✓	oct

JWS Algorithm Support

	Supported	alg values
RSASSA-PKCS1-v1_5	✓	RS256, RS384, RS512
RSASSA-PSS	✓	PS256, PS384, PS512
ECDSA	✓	ES256, ES384, ES512
Edwards-curve DSA	✓	EdDSA, Ed25519
HMAC with SHA-2	✓	HS256, HS384, HS512
Unsecured JWS	✓	none

JWE Key Management Algorithm Support

	Supported	alg values
AES	✓	A128KW, A192KW, A256KW
AES GCM	✓	A128GCMKW, A192GCMKW, A256GCMKW
Direct Key Agreement	✓	dir
RSAES OAEP	✓	RSA-OAEP, RSA-OAEP-256, RSA-OAEP-384, RSA-OAEP-512
PBES2	✓	PBES2-HS256+A128KW, PBES2-HS384+A192KW, PBES2-HS512+A256KW
ECDH-ES	✓	ECDH-ES, ECDH-ES+A128KW, ECDH-ES+A192KW, ECDH-ES+A256KW

JWE Content Encryption Algorithm Support

	Supported	enc values
AES GCM	✓	A128GCM, A192GCM, A256GCM
AES CBC w/ HMAC	✓	A128CBC-HS256, A192CBC-HS384, A256CBC-HS512

Unsupported Algorithms or Key Types

Due to the use of Web Cryptography API and runtime limitations the following is not supported in Bun:

• RSA1_5
• secp256k1 / ES256K
• Ed448
• X25519 and X448

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See also

• Browser Support
• Cloudflare Workers Support
• Deno Support
• Electron Support
• Node.js Support
• Vercel's Edge Runtime Support