I built JustOpenFile, a browser-based file viewer that processes files locally without uploading them to a server.
It supports PDF, DOCX, Excel, CSV, JSON, Markdown, EPUB, ZIP, SQLite, images,
audio, video, fonts, and 3D formats such as STL, GLB, and OBJ. ZIP archives
can also preview supported files inside them.
The project was motivated by a simple problem: opening an unfamiliar file
often requires installing an application or uploading potentially sensitive
data to an online service.
There is no account, installation, or upload required.
https://justopenfile.com
I’d appreciate feedback on file formats you would find useful and any
compatibility or performance issues you encounter.