Convert WebP to AVIF
Already on WebP and wondering if AVIF is worth it? For large hero images and photo-heavy pages, usually yes — AVIF shaves another 20–40% off. Be honest with yourself about the source though: your WebP was already lossy-compressed once, so this second re-encode is best done at moderate-to-high quality, or from the true original if you still have it.
Need the other direction? Convert AVIF to WebP
How it works
Drop in WebP files worth re-compressing — hero images and full-width photos, not 10 KB thumbnails.
Encoding runs at quality 65, deliberately higher than my from-original defaults, to keep this second lossy pass invisible.
Keep conversions that clear real savings in the readout, leave the small stuff as WebP, then download singles or the zip.
WebP vs AVIF
A match between the two modern formats, and AVIF wins it on points rather than by knockout: another 20–40% off files WebP already compressed. The catch is double-lossy stacking — converting only makes sense when the WebP is your only source and the image is big enough to matter.
| WebP | AVIF | |
|---|---|---|
| Compression | Lossy or lossless | Lossy or lossless |
| Transparency | Yes (full alpha) | Yes (full alpha) |
| Animation | Yes | Yes (rarely used) |
| Support | All current browsers (since 2020) | All current browsers (Safari since 16.4, 2023) |
| Best for | Web images: photos, thumbnails, UI assets | Hero images and photo-heavy pages |
Frequently asked questions
No — that is the whole reason I built this. The conversion runs in your browser using WebAssembly, so your files never leave your device; there is no server in the loop at all. It also means the tool keeps working offline once the page has loaded, and there is no file size limit beyond your device’s memory.
For big images where bytes matter — hero banners, photography, full-screen backgrounds — yes, expect another 20–40% savings. For small thumbnails and icons the absolute savings are tiny, and the double lossy re-encode is harder to justify. Convert where the bytes are.
Slightly, yes — the WebP already discarded some information, and AVIF discards a little more. That is why this tool defaults to quality 65, higher than my from-original tools. If you still have the original PNG or JPG, converting that directly to AVIF gives a better result.
If you support anything older than Safari 16.4 (March 2023), yes — serve both via a <picture> element with AVIF listed first. If your analytics show only current browsers, AVIF alone is fine.
Meaningful on the big stuff: a 300 KB hero image dropping to 200 KB is real; a 12 KB thumbnail dropping to 10 KB is noise. Check your network tab first, convert the top offenders, and leave the long tail as WebP. Both formats keep alpha, so nothing about transparency changes in the move.
A double-lossy chain on files you still have originals for. Re-encoding WebP into AVIF stacks two rounds of loss; converting the original via PNG to AVIF or JPG to AVIF reaches a smaller, cleaner file in one round. Use this tool when the WebP is genuinely all you have left.
Related tools
Convert AVIF to WebP
Convert AVIF to WebP in your browser — free, private, no upload. Keep files nearly as small while gaining years of compatibility with older browsers and tools.
Convert PNG to AVIF
Convert PNG to AVIF in your browser — free, private, no upload. AVIF keeps full transparency and beats even WebP on size, often 80–95% below the original PNG.
Convert JPG to AVIF
Convert JPG to AVIF in your browser — free, no upload, no signup. Photos come out roughly half the size of the JPEG at the same visual quality you started with.
Convert WebP to PNG
Convert WebP to PNG in your browser — free and lossless, transparency intact, no upload needed. Get a file that opens anywhere, from Photoshop to PowerPoint.