All aboard the AVIF train: I made a web app that converts images to and from AVIF

TL;DR: Go to to batch convert images to AVIF.

Unofficial logo animation for AVIF
An unofficial logo animation for AVIF

Recently, I heard about the new AVIF format.

Its features include alpha, lossy and lossless, HDR and many other goodies, but also offers better lossless compression than all web image formats, ? Impressive!

With support in Chrome, Firefox and Edge right around the corner, I decided to try it out. Unfortunately, I couldn’t find an easy, 1-click way to convert my existing images to AVIF. I either had to dive deep into the libavif library in C or use the cavif and davif command-line tools, with detailed documentation only in Japanese.

So, I made a web app for that!

Simply go to, drag & drop your images (or choose them from the file picker), and click on the avif chip to start converting. Your brand new AVIF files will be automatically downloaded after a few seconds. See a demo:

But do bear in mind that for larger images, it may take a minute or more for the conversion to complete. Be patient.

Under the hood, the converter uses cavif and davif, and supports PNG images both with and without alpha. Other supported image formats, which use ImageMagick, are JPEG, WebP, GIF, SVG, TIFF and ICO. It is also multithreaded for faster converting. The encoder’s CRF is set to 10, so that the produced images look (nearly) identical in quality to the original.

But it’s also a Progressive web app!

You can install it (or add it to your home screen) for quicker access.

After installing the PWA, on Chrome for Android and Edge for Windows 10, you can directly convert files from other apps and the File Explorer through the Share menu:

See it in action on Android
And on Windows 10