Verdict: AVIF wins on pure compression — it is often a fifth to a third smaller than WebP at equal visual quality — but WebP wins on compatibility and encoding speed. For web images today: use AVIF for large hero photos where every byte counts, and WebP as the safe everyday default.
| Criterion | WebP | AVIF |
|---|---|---|
| File size at equal quality | Larger than AVIF, still far smaller than JPG | Smallest of the mainstream web formats |
| Browser support | Universal in modern browsers since ~2020 | Modern browsers since ~2021–2022; older Safari lags |
| Encoding speed | Fast and cheap to generate | Noticeably slower to encode (decoding is fine) |
| Animation | Animated WebP is supported | No animation support — use WebP or video instead |
| Transparency | Yes, lossless and lossy alpha | Yes, alpha channel supported |
| Best for | The safe default for everyday web images | Maximum compression on large photos |
Every tool below runs entirely in your browser — your files never leave your device.
Yes, in most benchmarks AVIF files come out roughly a fifth to a third smaller than WebP at the same visual quality. The gap is biggest on detailed photographs and smallest on simple graphics.
All current Chrome, Firefox, Edge, and Safari versions support AVIF, but older Safari (before 16.4) and some in-app web views do not. Serve WebP or JPG as a fallback if you must reach those users.
Only the heavy images. AVIF encoding is slower, so convert hero and gallery photos where the byte savings pay off, and leave thumbnails and icons as WebP.
Yes — the linked converters above run entirely in your browser, so your images never leave your device and there are no per-file uploads.