The Short Answer
AVIF produces smaller files than WebP at the same quality — typically 20–30% smaller — and supports richer color and HDR. WebP has near-universal browser support, faster encoding, and is the safer default. In 2026, the practical answer for most websites is: use WebP as your baseline, and add AVIF where you can serve both with a fallback.
Both WebP and AVIF are 'next-gen' formats Google's PageSpeed Insights actively recommends over JPEG and PNG. Switching from JPEG to either one is a major Core Web Vitals win.
WebP vs AVIF at a Glance
The trade-off in one view before the detailed breakdown.
| Factor | WebP | AVIF |
|---|---|---|
| Size vs JPG | 25 to 35% smaller | Often around 50% smaller |
| Browser support | Near-universal | Broad and still growing |
| Encoding speed | Fast | Slower |
| Transparency | Yes | Yes |
| Best for | Default web use | Smallest files with a fallback |
File Size: AVIF Wins
AVIF uses the newer AV1 compression and consistently beats WebP on file size at equivalent visual quality. For photographic content, AVIF is often 20–30% smaller than WebP — and both are dramatically smaller than the original JPEG. Here's an illustrative example for a single product photo (your results will vary):
- Original JPEG (product photo): 1.8 MB
- WebP at quality 80: ~210 KB (-88%)
- AVIF at equivalent quality: ~150 KB (-92%)
Browser Support: WebP Wins
WebP is supported by essentially every modern browser and has been for years — Chrome, Firefox, Safari, Edge, and mobile browsers all render it. AVIF support is now strong (Chrome, Firefox, Safari, Edge) but slightly behind WebP, especially on older devices and some email clients.
For a public website in 2026, AVIF support is good enough to use — but you should still provide a fallback for the small percentage of clients that can't render it.
Encoding Speed: WebP Wins
AVIF's superior compression comes at a cost: it's significantly slower to encode than WebP. For a one-off image this is irrelevant, but when you're batch-converting hundreds or thousands of product images, WebP processes much faster. If you're optimizing a large catalog under time pressure, WebP gets you 90% of the benefit at a fraction of the processing time.
How to Serve Both (Best of Both Worlds)
The modern best practice is to serve AVIF to browsers that support it and fall back to WebP (then JPEG) for everything else, using the HTML picture element:
- 1Generate an AVIF and a WebP version of each image
- 2Use a <picture> element with AVIF first, WebP second, JPEG as the final fallback
- 3The browser automatically picks the smallest format it can display
If maintaining multiple formats sounds like a lot of work, start with WebP only — it already gives you 85–90% of the total savings. Add AVIF later when you have time.
Which Should You Choose?
Choose WebP if you want maximum compatibility, fast batch encoding, and a single format to manage — it's the pragmatic default for most stores and blogs. Choose AVIF when squeezing out every last kilobyte matters (image-heavy galleries, photography portfolios) and you can serve a fallback. For most BatchSet users optimizing product catalogs, WebP is the right starting point; AVIF is the power-user upgrade.