Concerns about the security of customer data have grown in tandem with the proliferation of cloud computing. While client-side encryption/decoding seems like a great way to keep sensitive data safe, the current setup has three major flaws: terrible usability due to specialised software and plugins that need specific types of terminals, low security due to low-entropy PIN encryption, and traditional encryption algorithms make data sharing a pain. This work creates and deploys WebCloud, an effective browser-side encryption solution, using state-of-the-art Web technologies. Not only does it fix all three of those problems, but it also handles data quickly with disconnected encryption and re-appropriated decoding, as well as a robust and rapid client denial. More specifically, our solution works on any device—desktop, mobile, or otherwise—that has a Web user agent installed. We combine complicated cryptographic operations using WebAssembly and the Web Cryptography API. Additionally, we build a file management application called WebCloud based on ownCloud. We conclude that WebCloud is successful and cross-platform after comprehensive testing with many popular browsers, Android applications, and PC software. The technology known as the ciphertext-policy attribute-based key encapsulation mechanism (CP-AB-KEM) is an integral component of the design of WebCloud and has the potential to be utilised in a variety of other contexts.