jsrsasign

The 'jsrsasign' (RSA-Sign JavaScript Library) is an opensource free cryptography library supporting RSA/RSAPSS/ECDSA/DSA signing/validation, ASN.1, PKCS#1/5/8 private/public key, X.509 certificate, CRL, OCSP, CMS SignedData, TimeStamp, CAdES JSON Web Signature/Token/Key in pure JavaScript. It can be used as follows:

This powerful tool is ideal for secure digital signing and encryption in web applications, providing a robust solution for managing digital identities and ensuring data integrity. Its versatility makes it suitable for a wide range of applications, from securing transactions to creating secure communication channels.