Dropdo, an online document browsing platform, is completely free.

Dropdo, an online document browsing platform, is completely free with an extremely simple and user-friendly interface. You can browse documents by uploading files or providing the web address of an online document. Dropdo supports many document formats including commonly used ones like Word, Excel, and PDF, as well as various image files. Additionally, you can share the documents with friends via a link for them to view and download. This is a convenient online tool; if you don't have desktop software installed, it's worth giving it a try.