Show HN: OnlyJPG – Client-Side PNG/HEIC/AVIF/PDF/etc to JPG https://ift.tt/XvAfJky

Show HN: OnlyJPG – Client-Side PNG/HEIC/AVIF/PDF/etc to JPG TL;DR: private, in-browser converter that turns pretty much any image file format into standard JPEGs. Everything runs locally. No uploads. This started as a five-minute job and forty hours later... I wanted to convert a HEIC without uploading it anywhere, so I wrestled Emscripten/WebAssembly to run Google's Jpegli inside a Web Worker. Now there's a small UI and it handles a bunch of formats. Just about the only thing it can't decode is JXL - but there's still some JPEG XL magic in there: XYB perceptual color quantization is enabled by default via Jpegli. The upside of all this over-engineering is privacy and compatibility: images are processed entirely on your machine and never touch a server; the output is a regular JPEG that works everywhere. I could have used a CLI, sure — but where's the fun in that? Would love feedback on edge cases and defaults. Tested on Firefox, Chrome, and Safari. Cheers! https://onlyjpg.com October 17, 2025 at 04:29AM