Cryptomator

AxCrypt

AxCrypt encrypts files and folders with AES-256 before they are stored or shared, integrating directly with cloud services like Google Drive, Dropbox, and OneDrive so encrypted files sync automatically. It combines file encryption with password management, secure text messaging, and shareable encrypted links, and has been in use for over 20 years across roughly 160 countries.

BestCrypt Container Encryption

BestCrypt Container Encryption, made by Finnish security vendor Jetico, creates encrypted virtual containers that behave like normal drives or folders for storing sensitive files. It is built to protect data placed in cloud-sync folders such as Dropbox: because the container is encrypted before it syncs, the underlying cloud provider and anyone who compromises the cloud account only ever sees encrypted bytes. The product works across Windows, macOS, Linux, and Android, and includes a portable BCTraveller tool for accessing encrypted containers on machines without BestCrypt installed. Jetico has built encryption and secure-wiping software for over 30 years and markets BestCrypt alongside its BestCrypt Volume Encryption and data-wiping product lines for endpoint data protection.

CryFS

CryFS is a free, open-source cryptographic filesystem that encrypts files locally before they are synced to cloud storage providers like Dropbox, Google Drive, iCloud, or OneDrive. Unlike tools that only encrypt file contents, CryFS also hides file sizes, file names, and the directory structure itself, so a compromised cloud provider cannot infer what is stored.

Folder Lock

Folder Lock, from NewSoftwares.net, is a longstanding Windows file-security application that lets users lock, hide, and encrypt files and folders using AES 256-bit encryption. It creates password-protected encrypted lockers that can live on local drives as well as sync to cloud storage such as Dropbox, Google Drive, and OneDrive, and it can send encrypted files by email in a self-contained format that recipients can open without installing the program. Beyond encryption, Folder Lock includes a file shredder for permanently deleting sensitive files and can clear Windows temporary files, clipboard data, program tracks, and media history. The vendor states it has more than 55 million users, and pricing is a flat one-time license (around $39.95) rather than a recurring subscription, with a free version also available.