Convert AVIF to WebP
Drop a AVIF file below and get a WebP back. The conversion happens on your own machine, so nothing is uploaded and there is no size or quantity limit beyond what your browser can hold in memory.
Drop images here
Ctrl/⌘ VPaste a screenshot or copied image
Accepts AVIF
Lower means a smaller file. 75 is a good default for photos.
100% in your browser Files are never uploaded.
Why convert AVIF to WebP?
Plenty of websites, content management systems and older desktop programs reject AVIF uploads outright. WebP is accepted just about everywhere, and that alone accounts for most of these conversions.
Expect the WebP file to come out larger than the AVIF you started with. That is the price of the broader compatibility and simpler decoding WebP gives you.
Both formats are lossy. Every re-encode discards a little more detail, so it is worth starting from the original rather than from a copy that has already been through this a few times.
This is a deliberate step backwards, and a sensible one. AVIF compresses better, but WebP has been shipping in every browser for years longer and reaches places AVIF still does not — older devices, in-app browsers, a long tail of software that updates slowly. Trading some efficiency for that reach is a reasonable decision, not a compromise.
Before you convert
Expect the file to grow by roughly a third
AVIF is meaningfully ahead of WebP on compression, so reversing that direction costs bytes. The exact figure depends on content — photographs show the biggest gap, flat graphics the smallest — but planning for something like a third larger is realistic. That is the price of the wider reach, and for many sites it is worth paying.
A second lossy pass, with the usual caveat
The AVIF already discarded detail and WebP now re-encodes what remains, artefacts included. If the original is available, encoding WebP directly from it will be both smaller and cleaner. And resist raising quality to protect the result — high settings make the encoder spend bytes preserving AVIF's compression artefacts precisely, which is not what you want to keep. Around 80 is the practical range.
Both support transparency, so nothing is lost there
Unlike a move to JPEG, the alpha channel comes across intact and there is no background colour to worry about. High bit depth and HDR are a different matter — WebP is 8-bit, so an HDR source will be flattened to standard range on the way through.
What carries over
- Transparency
- Pixel dimensions
- Reach into older browsers and devices
What does not
- Roughly a third to file size growth
- 10/12-bit colour depth and HDR
- A little detail — a second lossy pass
AVIF vs WebP at a glance
| Property | AVIF | WebP |
|---|---|---|
| Compression | Lossy | Lossy |
| Transparency | Yes | Yes |
| Typical file size | 40-55% of an equivalent JPEG | 65-75% of an equivalent JPEG |
| Compatibility | All current browsers; some older desktop apps lag behind | Supported by all current browsers and most apps |
| Usually comes from | Websites optimising page weight | Websites optimising page weight |
Frequently asked questions
Are my AVIF files uploaded anywhere?
No. The decoder and encoder are WebAssembly modules that run inside this page. The network tab may show a codec downloading the first time you use a format, but no request contains your file. On supported browsers, a codec that has already been used is cached so the same conversion can work offline.
Is there a file size or quantity limit?
There is no limit imposed by us. The practical ceiling is your device’s memory, since the image has to be held uncompressed while converting. On a typical laptop, images up to around 100 megapixels convert without trouble.
Will converting to WebP lose quality?
WebP is a lossy format, so some data is discarded. At the default quality setting the difference is not visible at normal viewing sizes. If you need an exact copy of the pixels, choose PNG instead.
Does it work on a phone?
Yes. The same WebAssembly modules run on mobile browsers. Conversion is slower than on a desktop because phone CPUs are weaker, and very large images are more likely to hit memory limits.
Where do AVIF files come from?
Almost always from a website. AVIF compresses better than anything else in wide use, so sites that care about page weight serve it. Cameras and phones do not produce it, which is why most people only meet AVIF when saving an image from the web.
Is WebP safe to use on a website?
Yes. Every current browser supports it, which covers roughly 97% of visitors. The remaining gap is old software rather than old browsers — a few desktop image viewers and older CMS upload forms still refuse it.