What this does
Converts AVIF images — the newest mainstream image format — into ordinary JPGs, locally in your browser. Drop up to 20 files, pick a quality, and download converted copies.
What is AVIF and why do I keep running into it?
AVIF is an image format derived from the AV1 video codec. It compresses
even better than WebP, so image-heavy sites and CDNs increasingly serve it
by default — which means "Save image as" hands you an .avif
file. Browsers open it fine; plenty of desktop apps, photo editors, and
upload forms still don't. Converting to JPG gets you back to universally
understood territory.
How does the conversion happen without an upload?
Your browser already ships an AVIF decoder (that's how it displays these images on the web). This page uses it to decode each file to a canvas, then re-encodes the canvas as JPG at the quality you choose. The decode and encode never leave your tab.
Why does my AVIF look slightly different as JPG?
Two possible reasons. First, AVIF supports wide color gamut and HDR; JPG output here is standard 8-bit sRGB, so highly saturated or HDR images get tone-mapped down. Second, both formats are lossy, so a second compression pass at low quality can soften detail — keep the slider at 85+ to make that invisible. If color fidelity is critical, prefer AVIF to PNG, which at least skips the second lossy step.
My browser says it can't decode the file — why?
Very old browsers (pre-2021 Chrome/Firefox, Safari before 16.4) lack AVIF support, and a few "AVIF" files are actually AVIF sequences (animations) that the still-image decoder rejects. Updating the browser fixes the first case; for animations, extract a frame with a video tool first.
Is my data private?
Yes — conversion is done by your own browser. No server sees your images, and nothing is retained when you close the tab.