Compress AVIF images
Make AVIF images even smaller. They stay AVIF and keep their transparency, and HDR photos keep their glow.
Drop images or folders hereAdd your images
JPG, PNG, WebP, AVIF, HEIC and GIF, up to 100 MB each
How it works
Compress in three steps
- 1
Drop your AVIF images in.
- 2
Graviton re-encodes them with libavif at a quality you choose, or to fit a file size.
- 3
Compare before and after, then download.
How AVIF compression works
Graviton decodes each AVIF and encodes it again with libavif, the widely used open-source AVIF library, at the quality you pick. Sharp color conversion keeps fine colored edges clean, and transparent areas stay transparent.
HDR photos stay HDR
An AVIF with an HDR gain map keeps it while “Keep HDR” is on, so the photo still glows on HDR screens and looks right everywhere else. Turn Keep HDR off under More options for a smaller, standard photo.
Frequently asked questions
Will my images stay AVIF?
Yes. Each image keeps its format and its file name. For apps and upload forms that can’t open AVIF, use AVIF to JPG.
Why does AVIF take longer than JPG?
AVIF squeezes more out of every pixel, and that takes more work. Graviton uses a faster encoder setting for large photos, so they stay quick to compress on phones too.
What if my AVIF is already compressed?
If no setting can make it smaller, Graviton gives you your original back, pixel for pixel, rather than a bigger file. Its metadata is still removed.
Are my images uploaded?
No. Graviton converts and compresses inside your browser, so your images never leave your device. Nothing is sent while you compress. When you download, the browser sends only a one-way fingerprint of the image, so the download can be counted and approved. Graviton stores none of it.
Is it free?
Yes. Compressing and converting are free and unlimited, with no account needed. Downloading needs a free account, which includes 3 downloads a day with every format and setting. Pro removes the daily limit.