I'm Nasa, and I built this tool because I was annoyed.
I kept needing to convert images — screenshots for documentation, product photos for a client, PNGs that needed to become WebPs before going on a site. Every online converter I tried worked the same way: upload your file, wait for it to travel to some server somewhere, wait for it to come back, download the result. For a 5-second task, the whole process took two minutes. And I had no idea what was happening to my files on the other end.
So I built my own. The first version was a 50-line script I ran locally. I made it a proper website when a few friends asked if they could use it too. That was about a year ago. It's still just me maintaining it.
When you drop a file into the converter, the conversion happens inside your browser using your own device's CPU. Nothing is sent to a server. Nothing is uploaded. Nothing is stored. The file goes from your computer into your browser's memory, gets converted, and comes back out as a download — all without touching the internet.
This is possible because modern browsers are genuinely powerful. HTML5 Canvas APIs can handle image encoding and decoding directly in the tab. For most format conversions, this is faster than the upload-wait-download approach anyway, because you skip the network entirely.
For more complex formats like AVIF — which requires heavier computation — I'm integrating WebAssembly (WASM) modules that allow near-native-speed processing in the browser. That's still in progress, but the goal is the same: everything stays local.
I'm not trying to be dramatic about it, but I do think it's worth being clear: a lot of "free" online tools make money by collecting the files people upload. That might mean using them for AI training datasets, selling metadata, or just retaining images longer than they claim to. The terms of service on most of these sites are long and vague on purpose.
Building a tool that processes locally removes that concern entirely. I can't collect your images because they never reach me. That's not a policy — it's a technical reality. You can verify it by opening your browser's network inspector while converting an image and watching that no file upload request is made.
AVIF conversion is the main thing I'm working on. The compression improvements over WebP are real and significant for photographs. The challenge is encoding speed — AVIF is computationally heavy, and I'm not willing to ship something that makes users wait 10 seconds for a conversion. The WASM implementation is getting there.
After that, probably batch conversion improvements and better handling of unusual color profiles and large files. I take bug reports seriously — if something isn't working for your specific use case, let me know.
The contact page comes directly to me. I read everything. Response time varies depending on how busy I am, but I try to reply within a few days. Bug reports, feature requests, and feedback about specific image types that aren't converting well are all useful.