With Google’s latest announcement that AVIF is now a supported file type in Google Search, the SEO community is buzzing about which image format—AVIF or WebP—should be the go-to recommendation for websites looking to optimize their image SEO.
Both formats have Google’s backing and offer significant advantages over older formats like JPEG and PNG.
However, there are key differences that SEOs need to consider when deciding which format to implement.
Understanding AVIF and WebP: A Quick Overview
WebP and AVIF are modern image formats that offer better compression and image quality than traditional formats.
While Google developed WebP, which has been around for several years and provides a balanced mix of quality, speed, and file size, AVIF was developed by the Alliance for Open Media (AOMedia). This consortium includes Google, Amazon, Netflix, Microsoft, and other tech giants.
AVIF, based on the AV1 video compression standard, offers superior compression and quality, making it an appealing choice for those who want to push the limits of image optimization.
How Do AVIF and WebP Compare?
When it comes to compression efficiency, image quality, and overall performance, here’s how the two formats stack up:
| Aspect | WebP | AVIF |
|---|---|---|
| Developer | Alliance for Open Media (AOMedia), including Google | |
| Compression Types | Lossy and Lossless | Lossy and Lossless |
| Compression Efficiency | Good (better than JPEG and PNG) | Excellent (better than WebP) |
| File Size | Small (but larger than AVIF for the same quality) | Smaller (best compression efficiency) |
| Image Quality | Good at moderate compression levels | Superior, especially for high dynamic range (HDR) |
| Browser Support | Supported by all major browsers | Supported by all major browsers (recent versions) |
| Transparency Support | Yes (with lossless compression) | Yes (with better efficiency than WebP) |
| Animation Support | Yes | Yes |
| Processing Speed | Faster encoding and decoding | Slower encoding and decoding |
| Compatibility | Well-supported across various platforms and tools | It is increasingly supported, but some tools are still catching up |
| Use Cases | General web use where the balance between quality and size is needed | Ideal for high-quality images with small file sizes (e.g., e-commerce, high-traffic sites) |
How Do Other Image Formats Compare?
While WebP and AVIF are modern, efficient choices for web optimization, other formats like JPEG, PNG, and GIF are still in use.
Here is a size comparison for a single 4K resolution image (3840 x 2160 pixels) across these formats:
| Format | Compression Type | Estimated File Size for a 4K Image (3840 x 2160 pixels) | Ideal Scenarios for Use |
|---|---|---|---|
| JPEG | Lossy | ~1 MB to 5 MB (depending on quality settings) | Photographs and images where slight quality loss is acceptable. It is good for sites needing small file sizes without transparency. |
| PNG | Lossless | ~15 MB to 25 MB | Graphics, images with transparency, or where quality must not degrade. Best for logos, icons, and simple graphics. |
| GIF | Lossless for stills; Lossy for animation | ~5 MB to 10 MB for stills; larger for animation | Simple animations, small icons, or images where colors are limited. Suitable for simple web animations but not recommended for complex or high-quality images. |
| WebP | Lossy/Lossless | ~0.5 MB to 3 MB (lossy), ~6 MB to 10 MB (lossless) | Web images where a balance between quality and file size is needed. It is ideal for most web applications, e-commerce, blogs, and news sites. |
| AVIF | Lossy/Lossless | ~0.2 MB to 1 MB (lossy), ~3 MB to 6 MB (lossless) | High-quality images with minimal file size, especially for high-traffic sites, mobile-first websites, and applications requiring excellent image quality. |
Ideal Scenarios to Use Each Format
- JPEG:
- When to Use: This is best for photographs where file size needs to be minimized, and slight quality loss is acceptable. It is also useful in situations where transparency isn’t needed.
- Drawback: Larger file sizes compared to WebP and AVIF for the same quality level.
- PNG:
- When to Use: This is ideal for images that require transparency, such as logo design and icons, or graphics that must retain lossless quality.
- Drawback: Significantly larger file sizes make it less suitable for use cases where speed is critical.
- GIF:
- When to Use: It is still used for simple animations or small, low-color images like icons and small graphics.
- Drawback: Limited to 256 colors, unsuitable for high-quality images or photographs.
- WebP:
- When to Use: It offers a good balance between quality and file size, making it ideal for general web use. It is suitable for blogs, news sites, and websites with mixed content types.
- Drawback: While efficient, it doesn’t achieve the same compression levels as AVIF.
- AVIF:
- When to Use: This is perfect for websites focused on speed and high-quality images. It is also ideal for e-commerce, portfolios, and high-traffic websites where compression efficiency directly impacts performance.
- Drawback: Slower encoding and decoding speeds; some tools and platforms are still catching up with full support.
Stan Ventures’ Recommendation for SEOs: WebP or AVIF?
Based on the benefits and trade-offs discussed, Stan Ventures recommends the following approach:
- Adopt a Dual-Format Strategy:
- Use AVIF as the primary image format for websites with critical compression and quality, such as e-commerce sites, portfolios, and high-traffic blogs.
- Provide WebP as a fallback format for older browsers or platforms that may not fully support AVIF. This can be achieved using the HTML
pictureelement or server-side logic to serve the best format based on the browser’s capabilities.
- Evaluate Your Website’s Needs:
- Due to its faster encoding and decoding times, WebP might be preferable for websites with dynamic content or a high volume of image processing. This format still significantly reduces file size compared to traditional formats.
- Monitor Browser and Platform Updates:
- As support for AVIF continues to grow, webmasters should monitor updates to browser capabilities and platform compatibility. Over time, transitioning more fully to AVIF will provide better performance benefits.
- Optimize for Core Web Vitals:
- AVIF’s superior compression can help reduce Largest Contentful Paint (LCP), a key metric in Google’s Core Web Vitals. For websites aiming to improve their SEO and user experience, using AVIF can be a decisive factor.
- Test and Analyze:
- Run A/B tests to compare your website’s performance of AVIF and WebP. To make data-driven decisions, look at metrics like page load speed, user engagement, and conversion rates.
The decision to use WebP or AVIF will depend on your website’s specific needs, the user experience you aim to provide, and your technical capabilities. By adopting a flexible strategy that leverages the strengths of both formats, SEOs can ensure that their websites are prepared for the future while maximizing both performance and visual quality today.
For more insights and expert advice on optimizing your website’s SEO, stay tuned to Stan Ventures!
Dileep Thekkethil
AuthorDileep Thekkethil is the Director of Marketing at Stan Ventures, where he applies over 15 years of SEO and digital marketing expertise to drive growth and authority. A former journalist with six years of experience, he combines strategic storytelling with technical know-how to help brands navigate the shift toward AI-driven search and generative engines. Dileep is a strong advocate for Google’s EEAT standards, regularly sharing real-world use cases and scenarios to demystify complex marketing trends. He is an avid gardener of tropical fruits, a motor enthusiast, and a dedicated caretaker of his pair of cockatiels.