ES256 (ECDSA P-256)
ES256 uses ECDSA with the P-256 curve and SHA-256. It provides equivalent security to RSA with significantly smaller key sizes, making tokens and keys more compact.
When to Use
Use ES256 when you want asymmetric signing with smaller keys than RSA, especially in mobile or bandwidth-constrained environments. Supported by most modern JWT libraries.
Key Length Requirements
P-256 curve (256-bit private key). Generate ECDSA key pairs with your language crypto library or OpenSSL.
Generate Keys
Recommended: asymmetric
Open Rsa Key GeneratorRelated Comparisons
Related Terms
Frequently Asked Questions
ES256 vs RS256?
Both are asymmetric. ES256 keys are smaller; RS256 has broader legacy support. Either is secure for new projects.
Is ES256 FIPS compliant?
P-256 is widely used in regulated environments. Confirm compliance requirements with your security team.