WebP to AVIF Converter
You already serve or store WebP and want to see whether AVIF treats your pictures better. This page converts a WebP to AVIF on your device so you can compare the two with your own files. It needs a browser that is able to write AVIF; if yours cannot, the AVIF button is disabled.
How to convert WEBP to AVIF
- Add your WEBP files by dropping them, clicking the drop zone or pasting.
- The output format is already set to AVIF. Adjust quality or size if you need to.
- Press Convert and compare the original and new size for each file.
- Download each file or all of them as a ZIP.
When to convert, and when not to
- You are tuning a website and want to compare formats on your real pictures before choosing one.
- Your hosting or image pipeline accepts AVIF and you need a file in that format.
- You can keep a fallback copy for visitors or tools that cannot open AVIF.
- Do not convert if the picture is going into email or an older program. AVIF support there is limited, and WebP or JPG is safer.
What changes
- Both formats are lossy by default, so the picture is compressed again and the quality slider sets how strongly.
- Transparency is kept, because AVIF can store it.
- Metadata is not copied to the new file.
- If your browser cannot encode AVIF, the AVIF option is disabled rather than silently giving you a different format.
- An animated WebP becomes one still image.
Comparing two modern formats on your own pictures
WebP and AVIF were both created to make web images lighter than JPG. Which one wins depends on the picture itself, the quality setting and the encoder doing the work. General claims are unreliable, so the useful test is to run your own files through both.
Convert a few representative images, such as a photo, a graphic with text and a cut-out with transparency. Compare the new size shown beside each file and open the results at full size to look for smearing or blocky patches. That small experiment tells you more than any comparison chart.
Keep a small test set so you can repeat the comparison later. A photo, a screenshot, a logo with transparency and a graphic with gradients cover most real situations. When a browser or encoder is updated, running the same four files again shows whether anything changed, without you having to read release notes or rely on anyone else's claims.
Why a converted image is compressed twice
A lossy WebP has already lost some detail. Turning it into AVIF decodes those pixels and compresses them again, so the second file inherits the first one's losses and adds its own. For the best result, start from the highest quality original you have, not from a WebP that was already squeezed.
If your original JPG or PNG is still around, converting that directly to AVIF will normally give a cleaner outcome than going through WebP first.
If you only have WebP files and no originals, set the quality slider fairly high so the second compression step adds as little as possible. Then judge the result by eye at the size it will actually be displayed. A difference that cannot be seen on the page where the image lives is rarely worth worrying about, whatever the numbers say.
What to do if AVIF is greyed out
This tool writes AVIF using your browser's own encoder. Not every browser includes one, and the page tests for it when it loads. When the test fails, the AVIF button is disabled and a short note explains why.
In that case try a current version of another browser on the same device. You can also choose WebP or JPG as your output, which every browser can create.
Remember that AVIF is read by browsers and software separately from the way it is written. Even when your browser can create AVIF files, a colleague's program may not open them. Before you replace anything in a live project, open the converted file in the other tools your team uses and confirm it displays correctly there too.
Privacy: your files stay on your device
- The tool decodes, resizes and encodes your pictures with your browser. The files are never sent to a server.
- To check it yourself: open the browser developer tools (F12), open the Network tab, convert a file, and look for any request that carries your image. You will see none.
Frequently asked questions
Why can I not select AVIF?
Your browser cannot encode AVIF, so the option is disabled. Try another current browser, or choose a different output format.
Will the AVIF always be smaller than my WebP?
Not necessarily. It depends on the picture and settings, so compare the sizes shown for your own files.
Does the AVIF keep transparency?
Yes. Transparent areas in the WebP remain transparent.
Can everyone open the AVIF file?
No. Some programs and older browsers cannot open AVIF, so keep a WebP or JPG copy for those cases.
Is my image sent to a server for conversion?
No. Everything happens locally in this browser tab.