JPG to AVIF Converter
Runs in your browser — your files are never uploaded.
Convert a JPEG to AVIF and usually cut its size by a third or more at the same perceived quality. This is the conversion AVIF was designed for — photographic content is exactly where it beats JPEG hardest. Encoding happens in your browser with a WebAssembly build of libavif, so the photo never leaves your device, and the result reports the real size change rather than assuming it went well.
OptionsQuality: 60% · Encoder effort: Balanced · Max width: Original size · Lossless: off
How to convert JPG to AVIF
- 1
Drop your JPG onto the box, or click to choose a file.
- 2
Leave quality at 60 — on AVIF that is roughly JPEG 85.
- 3
Click “Download”, and compare the reported sizes before replacing the original.
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Frequently asked questions
How much smaller will my JPEG get?+
Commonly 30–50% at matched visual quality, and sometimes much more on large photographs. The gain is smallest on images that are already heavily compressed — re-encoding a JPEG saved at quality 40 mostly preserves the artefacts it already has rather than finding new savings.
Does converting a JPEG to AVIF lose quality?+
Yes, a little — this is a lossy format re-encoding another lossy format, so the losses compound. It is not visible at sensible settings, but it is real. Always convert from the highest-quality source you have rather than from an already-compressed copy, and never re-convert the same file repeatedly.
What quality setting should I use?+
Start at 60. AVIF quality is not on the same scale as JPEG quality: 60 here corresponds to roughly JPEG 85. Values above 90 cost a great deal of encoding time and file size for detail that is not visible, and can even produce a file larger than the source.
Why does the first conversion take a moment?+
The encoder is about 3.5 MB of WebAssembly and downloads once per session, because no browser can encode AVIF natively. Every conversion after the first reuses it. That download is the price of encoding on your own machine instead of uploading the photo somewhere.
Should I use AVIF or WebP?+
AVIF generally produces smaller files at the same quality; WebP encodes far faster and is supported by a longer tail of older software. If you are optimising a website and can serve a fallback, AVIF first with WebP behind it is the usual arrangement. If you need one format that simply works everywhere today, WebP is the safer single choice.