AVIF to WebP converter

Both of these are modern formats and both compress well, so this is not a conversion about quality — it is about reach. AVIF is the more efficient of the two and the less widely understood: browsers handle it, but a great deal of other software does not. WebP has been around a decade longer and turns up in far more places, including image editors, CMS uploaders and messaging apps. Converting trades a modest amount of efficiency for a meaningfully larger set of things that will open the file.

When you actually need this conversion

• A CMS, a template or an upload form accepts WebP but rejects AVIF — common, because the validation lists were written before AVIF existed.
• You are handing images to someone whose tooling you do not control, and WebP is the safer assumption.
• You need transparency preserved and want a smaller file than PNG would give, without depending on AVIF support.

What to watch out for

• The file will grow, typically 20–40%. WebP is efficient but AVIF is more so, and that is the cost of the wider compatibility.
• This is a lossy-to-lossy re-encode. A single pass at quality 85 is not visible, but do not convert back and forth repeatedly.
• AVIF images with more than 8 bits per colour channel are reduced to 8 — WebP has no wider mode.

AVIF and WebP, side by side

How the conversion works here

Your file is decoded in a Web Worker inside this browser tab — by the browser's own image pipeline where it can, and by a WebAssembly build of libheif or libavif where it cannot. The decoded pixels are then re-encoded with Google's libwebp, the same encoder Squoosh uses.

All of that happens on the processor in front of you. There is no upload step, no queue and no server, which is why there is no size cap, no daily allowance and no paid tier — and why the whole thing keeps working with the network switched off.

Doing more than one thing

Most people converting a format also need it smaller or a different size. The result screen hands your converted files straight to the compressor or the resizer in one click — no second download, no re-selecting files. If you need several formats, the general converter lets you pick the output each time.