jsrsasign
End of support announced for 3 June 2026. jsrsasign is an open source free cryptography library written in pure JavaScript. It supports RSA, RSA-PSS, ECDSA, and DSA signing and validation, along with ASN.1 encoding and decoding. The library handles PKCS1, PKCS5, and PKCS8 private and public keys, X.509 certificates, Certificate Revocation Lists, OCSP, CMS SignedData, time stamping, and CAdES. It also provides full support for JSON Web Signature, JSON Web Token, and JSON Web Key. Designed to run in both browser and Node.js environments, jsrsasign enables developers to perform cryptographic operations and work with public key infrastructure standards entirely client-side or in server-side JavaScript without external dependencies.