AVIF to WebP Converter
A step back to the format that arrived first and got everywhere — without giving up transparency or falling all the way to a decades-old codec.
JPEG has no transparency, so transparent areas are filled with this color.
Everything runs locally in your browser. Nothing is uploaded to any server — close the tab and your files are gone.
How to convert AVIF to WebP
Add the AVIF images
WebP is already chosen as the output on this page. Whatever you drop is decoded and re-encoded right here, and each row shows what the file weighed before and after.
Start at 75 and move up rather than down
That is where the slider opens. The AVIF has already been through a lossy encoder once, so this is a second pass over pixels that lost something the first time — around 80 to 90 keeps that from showing, and the result is still nowhere near the weight of a lossless PNG of the same picture.
Trim the dimensions if this is a delivery file
The resize control fits the longest edge to 1024, 2048 or 4096 px before the encoder runs, and never enlarges anything. For an image headed into a layout or a page, that usually saves more than any movement of the quality slider does.
Inspect one file closely before trusting the rest
Open the compare slider and go to a gradient or a flat background. Stacked compression shows up there first, as banding or faint patches, while busy detail hides it well. If that area holds at your setting the batch will too — then download the rows one by one or as a ZIP.
Two modern formats, one of them older
The move is about where the file is accepted
Both formats compress far better than JPEG, so this conversion is not chasing efficiency — it is chasing reach. WebP shipped years earlier and had that head start to spread, and plenty of software and upload forms that reject an .avif outright will take a .webp without comment. That gap, not quality and not size, is the entire reason to run this.
The middle rung of the ladder
There are three places an AVIF can land and they are not interchangeable. WebP keeps the transparency and stays light, which is why it is the first thing to try. PNG keeps the transparency and adds nothing lossy, at several times the weight. JPEG is the one everything accepts and the one that flattens a cut-out onto a solid colour. Step down only as far as the destination actually forces you to. WebP, AVIF and JPEG compared compares the three on the same set of images if you want the numbers behind that order.
Lossy to lossy, so the loss adds up
Unlike the PNG route, this one hands the decoded pixels to another lossy encoder. What the AVIF discarded stays discarded, and the WebP pass removes a little more on top — some of its bits going to faithfully reproduce the smoothing the first encoder left behind. At a sensible quality it is a small effect once, and a compounding one if the same image keeps being re-encoded, which is why the AVIF is worth keeping as the master.
Transparency comes along, and so does some weight
Both formats carry an alpha channel, so a cut-out stays a cut-out: nothing is flattened and no fill colour is chosen, which is the practical difference between this route and converting to JPEG. The size usually rises a little, since AVIF compresses harder than WebP at a comparable look, but it is a far shorter step up than PNG would be — and each row prints its own before and after with a smaller or larger label.
Two decoders, so odd files still get through
Each AVIF is handed to the dedicated decoder first, and if that refuses the file the browser’s own image decoder gets a turn. Between them most real-world files convert, including ones an editor has already given up on. When both fail the row simply reports a decode error and the rest of the batch keeps going.
When not to bother
If everything the image is headed for already reads AVIF — a modern site, a current browser, a CDN that serves what it is given — this conversion costs you a little quality and a few kilobytes and buys nothing. Check one file against the destination before you queue four hundred. The trip back is the expensive one: our AVIF encoding timings shows what encoding to AVIF actually takes on a normal laptop.
AVIF to WebP — frequently asked questions
Why would I go from AVIF back to WebP?
Because something in the way will not take the AVIF. WebP is the older of the two and reached far more software, so it is the fallback that usually gets through while still being much more efficient than JPEG. If everything in your chain already reads AVIF, there is nothing to gain here.
Which of the two is more widely supported today?
In current browsers, both — the difference has closed there. Outside the browser it has not: WebP arrived years earlier and had time to reach desktop applications, office and messaging tools, and the extension allow-lists that upload forms are built from. That head start is the whole reason this page exists.
Does the WebP end up bigger than the AVIF?
Usually a little, because AVIF is the more efficient codec of the pair. It is a far gentler increase than going to PNG, which stores every pixel losslessly. Each row shows the actual before and after, and a WebP that happens to come out smaller is labeled that way too.
Do I have to pick a background colour for the transparent parts?
No, and no swatch appears — that control shows up only when JPEG is the output. WebP has an alpha channel of its own, so transparent and semi-transparent pixels are encoded as they are, with nothing composited behind them.
Is converting twice worse than converting once?
Yes, in the sense that every lossy pass takes something and no pass gives anything back. One AVIF to WebP conversion at a reasonable quality is not something you would pick out by eye; the same image cycled between formats over and over is. Convert from the AVIF each time rather than converting a file that has already been converted.
Would I be better off re-exporting from the original instead?
Yes, whenever the original is still within reach — a layered document, a camera file, a design source. Exporting WebP from there is one generation of compression instead of two. This page is for the common case where the AVIF is all you have, because it came off a website or arrived in a handover.
Will an animated AVIF stay animated?
No. The output here is a single still WebP. Animated WebP is made on a different page — the GIF maker builds one from a set of frames, and the video converter from a clip — so if the motion is the point, hold on to the AVIF.
Why is the first AVIF slower than the ones after it?
The AVIF decoder is a separate WebAssembly module, fetched the first time one of these files appears, so the first conversion waits for that download and the rest of the batch reuses it. Only decoding is involved on this page — the slow half of AVIF is its encoder, and nothing here runs it.