WebP vs AVIF: What's the Difference?
WebP and AVIF are both modern image formats that compress better than JPG and PNG, but AVIF is newer and usually more efficient. AVIF, based on the AV1 video codec, often produces smaller files than WebP at the same quality, with better detail retention and support for wide color and HDR. WebP is older, encodes faster, and has slightly broader, longer-established support. Many sites serve AVIF first, then WebP, then JPG as fallbacks, getting the smallest possible file each browser can display.
- WebP
- Google format (2010); ~25–35% smaller than JPG; fast, universally supported (web.dev)
- AVIF
- Based on the AV1 codec; often smaller than WebP at equal quality, with HDR/wide-color support (AOMedia)
- Encoding speed
- WebP encodes faster; AVIF encoding is slower and more CPU-intensive
- Support
- Both supported in current Chrome, Firefox, Safari, and Edge
- Best practice
- Serve AVIF, then WebP, then JPG fallback via the picture element
What WebP and AVIF are #
WebP and AVIF are next-generation raster image formats designed to shrink web images below what JPG and PNG can achieve. WebP, released by Google in 2010, was the first widely adopted modern format, offering roughly a quarter to a third smaller files than JPG plus transparency and animation. AVIF, standardized more recently, is derived from the AV1 video codec and pushes compression further, frequently beating WebP at the same visual quality while adding support for high dynamic range and wide color gamuts. Both are lossy or lossless and both support transparency, so either can replace JPG and PNG. The key difference is that AVIF generally squeezes files smaller but takes longer to encode, while WebP is faster to produce and has a slightly longer track record of support. For any serious /services/speed-optimization effort, both are tools to cut image weight, and understanding their trade-offs lets you layer them so each visitor gets the smallest file their browser can render.
The compression comparison #
AVIF usually wins on raw compression. At a given perceived quality, AVIF files are often smaller than WebP, and both are much smaller than JPG. AVIF is particularly strong at preserving detail and avoiding the blocky artifacts that appear when you compress a JPG aggressively, and it handles gradients and flat areas cleanly. WebP still compresses very well and comfortably beats JPG, but on many images AVIF edges it out, sometimes significantly for photographic content. The exact difference varies by image; some images favor AVIF strongly, others show only a modest gap. For an image-heavy site where every kilobyte affects Largest Contentful Paint, AVIF's extra savings can be worthwhile. The practical approach is to generate both and serve AVIF first with WebP as the next fallback, so browsers that support AVIF get the smallest file and the rest get WebP. Measuring the real difference on your own images with /tools/image-compressor and /tools/website-grader is the best way to judge the payoff for your site.
Encoding speed and tooling #
The main practical cost of AVIF is encoding. Producing an AVIF file is more CPU-intensive and slower than producing a WebP, which matters if you generate images on the fly or process large batches. WebP encodes quickly and is supported by a wide range of long-established tools, making it easier to slot into existing pipelines. AVIF tooling has matured rapidly and is now widely available in modern image processors, CDNs, and build tools, but you should confirm your workflow supports it before committing. For most small businesses this is handled by a plugin, CDN, or hosting configuration rather than manual encoding, so the speed difference is invisible in day-to-day use. If your images are pre-generated once and cached, AVIF's slower encoding is a one-time cost with ongoing size benefits. When set up through /services/managed-hosting or a build pipeline, both formats can be generated automatically at upload, letting you enjoy AVIF's savings without worrying about the encoding overhead yourself.
Browser support today #
Both formats enjoy broad support in current browsers. WebP has been supported across Chrome, Firefox, Edge, and Safari for years, giving it a slightly longer, more universal track record, including in older device versions. AVIF is supported in current versions of all major browsers as well, though support arrived later, so a small share of visitors on older browser versions may not see AVIF. This is exactly why the layered fallback approach exists: you serve AVIF to browsers that support it, WebP to those that support WebP but not AVIF, and JPG or PNG to anything older. The browser automatically selects the first format it can display, so every visitor sees an image and most get a modern, compact one. Because the fallback is invisible and automatic, adopting AVIF carries no risk of broken images. For businesses on a /services/care-plans arrangement, keeping this format negotiation configured is routine maintenance that quietly keeps images fast for everyone.
Serving both with fallbacks #
The picture element lets you offer several formats in priority order. List AVIF first, then WebP, then a JPG fallback in the img tag; the browser picks the first it understands. This delivers the smallest possible file to each visitor while guaranteeing compatibility. Here is the standard multi-format pattern.
<picture>
<!-- Smallest, newest format first -->
<source srcset="hero.avif" type="image/avif">
<!-- Next best if AVIF unsupported -->
<source srcset="hero.webp" type="image/webp">
<!-- Universal fallback -->
<img src="hero.jpg" alt="Storefront at dusk"
width="1600" height="900" loading="lazy" fetchpriority="high">
</picture>Impact on page speed and vitals #
Both formats improve page speed by reducing image weight, which directly benefits Core Web Vitals. AVIF's smaller files can lower Largest Contentful Paint even further than WebP, particularly for large hero images on mobile connections where every kilobyte counts. Lighter images also reduce total page weight, helping pages become interactive sooner and saving visitors' data. Since Google treats Core Web Vitals as a ranking factor, these gains support SEO alongside user experience and conversion. The biggest wins come from converting your largest, most prominent images, then combining that with correct dimensions, lazy loading below the fold, and a high fetch priority on the main image. Layering AVIF and WebP through the picture element ensures each visitor gets the fastest version their browser supports. A before-and-after check with /tools/website-grader quantifies the improvement. For image-heavy sites pursuing /services/speed-optimization, adding AVIF on top of WebP is a low-risk way to extract additional speed from assets you already have.
Which to choose for your site #
For most sites the answer is both, layered by preference, rather than one or the other. Serve AVIF first for the best compression, WebP next for broad support and fast encoding, and JPG or PNG as the universal fallback. This gives every visitor the smallest file their browser can display with no compatibility risk. If your tooling or platform only easily supports one modern format, WebP is the safer minimum because it encodes quickly and has the longest established support, while AVIF is the choice when you want maximum savings and your pipeline handles it. There is rarely a reason to pick only AVIF and drop WebP, since WebP is a valuable middle fallback. For a small business, the decision is usually made by the platform or CDN you use; a /services/speed-optimization review can confirm whether AVIF is worth enabling for your specific images. The guiding principle is to add formats in layers, not to gamble on a single one.
Setting up modern image delivery #
Implementing AVIF and WebP well is mostly a configuration task once the pipeline exists. Use an image CDN, a CMS plugin, or a build tool that automatically generates AVIF, WebP, and JPG variants at upload and serves them via content negotiation or the picture element. Always resize images to their real display dimensions first, since format optimization cannot rescue an oversized image, and apply lazy loading to below-the-fold images and a high fetch priority to the main above-the-fold image. Cache the generated variants so AVIF's slower encoding is a one-time cost. On WordPress and similar platforms, this is often a single plugin or a /services/managed-hosting setting. After enabling it, re-test with /tools/website-grader and monitor Core Web Vitals to confirm the gains. Done once, this pipeline makes every future image fast automatically, which is why modern image delivery is a standard component of any thorough /services/speed-optimization engagement rather than a per-image chore.
Common mistakes to avoid #
A few missteps undermine the benefits of these modern formats. The first is over-compressing: pushing AVIF or WebP quality too low to chase tiny files introduces smearing and banding that looks worse than a well-made JPG, so tune quality visually rather than blindly. The second is forgetting fallbacks; serving only AVIF can break images for the small share of visitors on older browsers, so always include WebP and a JPG or PNG in the picture element. The third is optimizing format while ignoring dimensions, since a huge image squeezed into a thumbnail still wastes bandwidth; resize first, then convert. The fourth is skipping lazy loading and fetch priority, which control when images download and matter as much as their size for perceived speed. Finally, do not re-encode already-lossy images repeatedly, as each pass degrades quality. Avoiding these traps, and confirming the right format is actually served by inspecting network requests, ensures your /services/speed-optimization work delivers the full speed benefit rather than a fraction of it.
FAQ
Is AVIF better than WebP?
AVIF usually compresses smaller than WebP at the same quality and supports HDR and wide color, so it is often technically better for photos. However, WebP encodes faster and has slightly broader established support. The best approach is to serve AVIF first with WebP as a fallback, getting AVIF's savings without giving up compatibility.
Do I have to choose between WebP and AVIF?
No. The recommended pattern is to serve both, layered by preference: AVIF first, then WebP, then JPG. The browser picks the smallest format it supports, so AVIF-capable browsers get the smallest file and others fall back gracefully. There is rarely a reason to drop WebP entirely, since it is a useful middle fallback.
Does AVIF work in Safari?
Yes, current versions of Safari support AVIF, as do current Chrome, Firefox, and Edge. Support arrived later than WebP, so a small share of visitors on older browser versions may not see AVIF. Using a picture element with WebP and JPG fallbacks ensures those visitors still get an image.
Why is AVIF encoding so slow?
AVIF is based on the AV1 video codec, which uses advanced, computationally heavy compression to achieve smaller files. That makes encoding more CPU-intensive and slower than WebP. In practice you generate AVIF once and cache the result, so the slower encoding is a one-time cost offset by ongoing smaller file sizes and faster page loads.
Will AVIF improve my page speed?
It can. AVIF's smaller files reduce image weight and may lower Largest Contentful Paint more than WebP, especially for large images on mobile. The gains are biggest on image-heavy pages. Combine AVIF with proper sizing, lazy loading, and fallbacks, then measure before and after to confirm the improvement on your specific site.
Which format should a small business use?
Serve AVIF, then WebP, then JPG as fallbacks so every visitor gets the smallest file their browser supports. If your platform only easily handles one modern format, WebP is the safe minimum. Most small businesses get this automatically through an image CDN, a plugin, or a managed hosting configuration rather than manual work.
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