File conversion tends to live in the awkward space between “I’ll only need this once” and “I need this all the time,” and the usual answer is to bounce between command-line utilities, desktop apps, and untrusted online converters. ConvertX starts from a very familiar self-hosted mindset: what if all of that lived in one place, on your own server, behind a simple web interface you could actually rely on?
What is ConvertX?
ConvertX is a self-hosted online file converter built for people who deal with a lot of files and formats and would rather keep that work on their own infrastructure. At its core, it’s a web-based interface that lets you upload files, convert them into other formats, and download the results without relying on third-party SaaS tools. It’s written in TypeScript and runs on Bun with Elysia, which already gives a hint about the kind of audience it’s aimed at: developers and self-hosters who enjoy modern tooling and fast runtimes.
ConvertX supports well over a thousand different formats, and that number doesn’t come from a single bloated dependency. Instead, it acts as a clean wrapper around a wide range of well-known conversion tools. You’ll see familiar names like ImageMagick, FFmpeg, LibreOffice, Pandoc, Calibre, Inkscape, and many others. Each one handles a specific domain, whether that’s images, documents, ebooks, video, vector graphics, or even 3D assets.
You upload one or more files, choose the output format, and let the backend handle the rest. Batch processing is supported, which is useful if you’re converting large collections of images or documents. There’s also support for multiple user accounts and password protection, which makes it viable for shared environments such as a small team server, a homelab used by family members, or an internal tool at work.
Image workflows are especially well covered, with ImageMagick, GraphicsMagick, Vips, libheif, resvg, Potrace, and VTracer all available. Video conversion is handled through FFmpeg, giving access to hundreds of input and output formats. Documents and text-based formats are covered by LibreOffice, Pandoc, XeLaTeX, and Calibre, which opens the door to everything from simple DOCX to PDF conversions to more niche tasks like ebook or LaTeX workflows. There are even utilities for things like Outlook messages, contact files, data formats, and SVG generation.
The project’s GitHub repository includes a Docker Compose setup that covers the full service, making it easy to spin up on an existing server without much manual configuration. If you’re already comfortable running containers, deployment is mostly a matter of pulling the images and starting the stack. The official instructions are documented in the ConvertX README on GitHub
Jeremy
Because ConvertX is self-hosted, it fits neatly into the broader self-hosting mindset. You control where files are stored, how long they’re kept, and who has access. For people who regularly upload sensitive documents or proprietary media to online converters, that alone can be reason enough to run something like this locally.
ConvertX focuses on bringing a wide set of proven tools under one consistent web interface, with sensible features like accounts and batch jobs layered on top. If you’ve ever wished your homelab had a single place to handle “convert this into that,” ConvertX feels like a practical and thoughtful attempt to solve that exact problem.
Be sure to visit the ConvertX Github to give the project a star!
Jeremy
Discussion