Convert PNG to AVIF
The smallest files you can get. Transparency supported, and photographs often drop by 80% or more.
Or drop images here
AVIF gives the biggest savings
AVIF is the most efficient image format in wide browser support. Against JPEG it is typically 40–50% smaller; against a PNG photograph the reduction is often 80% or more.
It handles the two things that trip up other formats particularly well: smooth gradients, which WebP can render with visible banding at aggressive settings, and dark areas, where JPEG tends to produce blocky artefacts.
The trade-off is encoding time
Browsers do not include an AVIF encoder. ShrinkFox downloads a WebAssembly encoder the first time you select AVIF, which takes a few seconds, and each image then takes roughly one to three seconds to encode depending on its size.
Converting five hero images is quick. Converting five hundred product photos will take a while, and you should leave the tab open while it runs. If you need speed more than the last 10% of file size, WebP encodes almost instantly and is the pragmatic choice for large batches.
Quality numbers are not comparable across formats
This is the mistake most people make with AVIF. Quality 80 in AVIF is not the same as quality 80 in JPEG or WebP — it is close to visually lossless and produces much larger files than you need.
Use lower numbers than you are used to:
| Content | AVIF quality |
|---|---|
| Large hero and background images | 50–60 |
| Product and general photography | 60–70 |
| Images containing text | 70–80 |
| Graphics with flat colour | Use PNG or lossless WebP instead |
Starting at 60 and raising it only if you can see a problem will get you the best results. Many people leave AVIF at 80 and wonder why their files are barely smaller than WebP.
Transparency works
AVIF supports an alpha channel, so transparent PNGs convert cleanly with the transparency intact. It also handles high dynamic range and wide colour gamut, though neither matters much for typical website images.
Where AVIF is not worth it
Small images. Below roughly 500 px, AVIF's container overhead eats into the compression advantage, and below about 200 px it can produce larger files than WebP.
Anything you upload elsewhere. Social platforms, marketplaces and most CMS installations either reject AVIF or transcode it immediately, so you gain nothing.
Large batches on a deadline. The encoding time is real. Weigh it against the saving.
Serving both AVIF and WebP
If you control your site's HTML, the picture element lets each browser pick what it supports:
<picture>
<source srcset="photo.avif" type="image/avif">
<source srcset="photo.webp" type="image/webp">
<img src="photo.jpg" alt="Description">
</picture>Run your batch three times with a different output format each time, and you have all three versions.
Related: PNG to WebP and our comparison of WebP vs AVIF.
Frequently asked questions
Is AVIF supported by all browsers?
It is supported by all current major browsers including Chrome, Firefox, Safari and Edge. Very old browser versions will not display it, which is why the picture element with a WebP or JPEG fallback is worth using.
Why is AVIF conversion slower than WebP?
Browsers include a WebP encoder but not an AVIF one, so a WebAssembly encoder is downloaded first. AVIF encoding is also far more computationally intensive by design.
What quality setting should I use for AVIF?
Lower than you would for JPEG or WebP. Start at 60 for photographs and raise it only if you can see a problem. AVIF at 80 is near-lossless and much larger than necessary.
Does AVIF support transparency?
Yes, it has a full alpha channel, so transparent PNGs convert without losing their transparent background.
Should I use AVIF for every image on my site?
No. It is best for large photographs. For small images, icons and thumbnails the savings shrink or reverse, and WebP is the better choice.
Can I upload AVIF to Shopify or WordPress?
WordPress supports AVIF from version 6.5 onwards. Shopify does not accept AVIF uploads at present. Use WebP for both if you are unsure.