How to Optimize WordPress Images with WebP and AVIF for Better Speed and SEO

If your WordPress site feels sluggish or scores poorly on PageSpeed Insights, there’s a high chance unoptimized images are to blame. Image files often make up over 60% of a page’s weight—and that means slow load times, poor SEO performance, and frustrated users. Whether you’re running an agency or managing multiple WordPress projects, efficient image handling is no longer optional.

To understand how big this impact could be, I converted a JPG image into various other file formats, and the difference is huge!

I mean, loading one PNG file is equivalent to loading 37 AVIF files on a page – Imagine.

If we look at image usage statistics, modern formats like WebP, celebrated for efficient compression, are gaining ground at 9.1%. AVIF emerges as another rising star gaining traction, currently adopted by just 0.1% of websites. 

Though support for these formats is not much at present, the best WordPress hosting for agencies supports them already. The good news is – WordPress, from version 6.6, has extended support for AVIF and WebP. 

Next-gen formats like AVIF and WebP can dramatically improve WordPress site optimization, helping you speed up load times, reduce bandwidth, and boost your site’s performance metrics across the board.

In this article, we explore why AVIF, alongside WebP, represents the future of image optimization for WordPress sites. More importantly, we will explain how you can check if your WordPress hosting supports these image formats and how to create WebP/AVIF files.

Understanding WebP, AVIF, and Other Image Formats

Often, website owners and WordPress developers do not understand the world of image formats, so we will begin from there. Let’s figure out how various famous image formats differ and when to use WebP or AVIF (or other image formats).

What are WebP and AVIF?

WebP is a modern image format developed by Google that offers superior compression without compromising quality. It aims to reduce file sizes significantly while maintaining high image quality, making it an ideal choice for web developers looking to optimize their sites.

• Excellent Compression: Reduces file sizes while maintaining image quality.
• Supports Transparency: Handles transparent images like PNG but with smaller file sizes.
• Animation Support: Can replace GIFs with better compression and quality.
• Lossy and Lossless: Offers both compression types for different needs.
• Wide Compatibility: Supported by most modern browsers and applications.

On the other hand, AVIF (AV1 Image File Format) is an even newer image format that provides exceptional compression and image quality. It offers impressive file size reductions and supports advanced features like high dynamic range (HDR) imaging with the help of the AV1 video codec.

• Superior Compression: Achieves smaller file sizes than WebP with similar or better quality.
• High Dynamic Range: Supports HDR images, offering better color depth and contrast.
• Efficient for Storage: Ideal for websites with lots of images, as it compresses better.
• Modern Browsers Support: Increasingly supported by major browsers.
• Advanced: Supports both lossy and lossless compression, transparency, and animations.

WebP vs AVIF: Which Format Should You Use for WordPress Image Optimization?

Choosing the right image format is essential for WordPress performance—and when it comes to modern formats, the two heavyweights are WebP vs AVIF. Both offer major improvements over traditional image types like JPEG and PNG, but they serve slightly different needs.

So, AVIF or WebP—which one is better for your site? Let’s explore the differences and use cases.

This AVIF vs WebP comparison shows that while WebP is more broadly supported and faster to encode, AVIF takes the lead in compression and quality—especially for high-resolution images.

When to Use WebP in WordPress

WebP is widely supported by all major browsers, making it the go-to format for most general use cases in WordPress:

• Blog images, featured images, and thumbnails
• E-commerce product images
• Backgrounds, sliders, and hero sections
• Image-rich pages where compatibility is key

Thanks to native support in WordPress (since version 5.8), it’s easier than ever to integrate WebP into your image workflow using plugins or CDNs.

When to Use AVIF in WordPress

AVIF WordPress implementations are gaining traction due to the format’s smaller file sizes and HDR capabilities. AVIF is ideal for:

• Photography portfolios and creative websites
• Sites with many high-resolution images
• Projects where performance and Core Web Vitals are critical
• Advanced visual needs (gradients, HDR, animations)

However, AVIF encoding can be slower, and browser support—while growing—is not as widespread. For best results, pair AVIF with a fallback to WebP.

Why Your WordPress Website Should Use WebP and AVIF (Instead of JPEG and PNG)

Still serving images in JPEG or PNG on your WordPress site? That could be silently killing your performance. While these traditional formats were once industry standards, they simply can’t keep up with today’s demands for speed, SEO, and responsive design.

Switching to modern formats like WebP and AVIF isn’t just a trend—it’s a performance upgrade. Here’s why developers, agencies, and site owners should make the switch.

1. WebP and AVIF Offer Dramatically Better Page Load Times

Speed is king—and WebP vs AVIF both outperform JPEG and PNG when it comes to compression. AVIF delivers up to 50% smaller files than JPEG at the same quality, while WebP slashes image sizes compared to PNG without losing transparency support.

• JPEG/PNG: Slower load, heavier files
• WebP/AVIF: Smaller size, faster rendering
• Result: Faster page loads and lower TTFB (Time to First Byte)

Whether you’re building a high-traffic blog, portfolio, or eCommerce store, using AVIF or WebP helps you keep users engaged and bounce rates low.

2. SEO Gains You Can’t Ignore

Search engines reward fast-loading websites, especially after Google’s Core Web Vitals update. Using WebP or AVIF in WordPress can directly improve:

• LCP (Largest Contentful Paint) — faster image load = higher score
• CLS (Cumulative Layout Shift) — optimized sizes reduce layout shift
• TTFB and PageSpeed — overall better metrics

Better scores = better rankings = more traffic. It’s that simple.

3. Better Image Quality at Lower File Sizes

Unlike JPEG, which suffers from visible artifacts at lower compression levels, and PNG, which results in huge file sizes with transparency, WebP and AVIF offer the best of both worlds:

• WebP: Great for everyday use, supports lossy/lossless, transparency, and animation
• AVIF: Ideal for image-rich or design-focused sites thanks to HDR support, finer gradients, and unmatched compression

Your WordPress site will look sharper, load faster, and feel more premium—without the performance trade-off.

4. Significant Bandwidth and Resource Savings

Every byte counts, especially for mobile users or visitors on slow connections. Replacing JPEG and PNG with AVIF or WebP reduces total page size and data transfer, leading to:

• Faster mobile experiences
• Lower hosting costs
• Fewer CDN hits or image delivery fees

If you’re managing multiple client sites, this adds up fast—saving time, money, and frustration.

Does WordPress Support AVIF/WebP for your Client Site?

Before recommending AVIF or WebP to your clients, it’s essential to confirm that their WordPress setup supports these modern image formats. While WordPress (since version 6.6) has built-in support for AVIF and WebP, your hosting environment, PHP version, and server libraries all play a role in making them work seamlessly.

In this section, we’ll walk you through the exact steps to verify compatibility and ensure optimal image delivery—whether you’re working on a staging environment or a live site.

Step 1: Try Uploading a File

The simplest way to check WordPress AVIF or WebP support is by uploading a WebP or AVIF image to your WordPress media library. For this:

Go to Media > Add New Media File to do so.

If the upload is successful, your site likely supports the format. If you encounter an error, it’s time to dig deeper.

Step 2: Check PHP Version

PHP. Watch suggests that PHP 8.1 and later versions include the GD extension with AVIF support, but the GD extension must be compiled with AVIF support. So, if your best WordPress managed hosting provider or cloud staging platform claims to support WebP and AVIF, while you still face issues, your PHP version might be the culprit. 

In case you want to use an older PHP version, ensure your server has the necessary libraries installed.

To check your PHP version:

1. Go to your WordPress dashboard.
2. Navigate to Tools > Site Health.
3. Click on the Info tab and scroll to the Server section.

If your PHP version is below 8.1, you’ll need to upgrade. Many hosts allow you to change your PHP version through their control panel.

If you use InstaWP, it’s easy to upgrade your site’s PHP version in the blink of an eye.

For a staging site, click on its name and change the PHP version from the dropdown in the PHP Config settings.

For a site hosted with InstaWP Live, you can go to the site’s dashboard and update your site’s PHP version in less than a second.

Step 3: Use WP CLI to Check Server Support

PHP version seems ok, but still, WordPress AVIF support or WebP isn’t working?

For a more thorough check, use WP-CLI (WordPress Command Line Interface) to verify if your server supports WebP and AVIF. Here’s how:

1. Access your server via SSH.

Note: InstaWP users can save a custom command and run it from their dashboard itself. 

Run the following command to check for supported image formats:

wp eval 'var_dump(gd_info());'

Alternatively, you can use the following command too:

php -i

2. Look for “WebP Support” and “AVIF Support” in the output.

If either is missing, it’s time to consult your hosting provider or consider switching to a host like InstaWP Live that offers full support for these modern formats.

InstaWP Live: Optimized Hosting for Modern Image Formats

InstaWP Live’s seamless integration of AVIF and WebP support means you don’t need to worry about technical complexities; simply focus on creating great content while InstaWP Live handles the optimization behind the scenes.

In case you don’t know – InstaWP Live is a managed WordPress hosting service optimized for speed, reliability, and ease of use. Designed specifically for WordPress sites, it offers features such as edge caching, built-in CDN, and global data centers, ensuring your website performs at its best.

AVIF and WebP Support on InstaWP Live (Managed WordPress Hosting)

InstaWP Live fully supports modern image formats like AVIF and WebP. These formats are seamlessly integrated into the platform, providing optimized image-handling capabilities. This support enhances website performance by reducing image sizes without compromising quality, leading to faster load times and improved user experiences.

Technical Capabilities and Server-Side Requirements

InstaWP Live’s infrastructure includes updated PHP versions and essential libraries like libavif and libwebp. This ensures compatibility and efficient processing of AVIF and WebP images. The service’s technical robustness ensures that your WordPress site benefits from the latest advancements in image optimization technology.

How to Create a WebP or AVIF File?

Creating WebP and AVIF files is straightforward with various online tools and software options available. Here’s how you can easily convert your images to these modern formats.

Method #1: Online Tools

For quick and easy conversions, online tools like Squoosh and Convertio are excellent options. Just upload your image, choose WebP or AVIF as the output format, and download the converted file. These tools are user-friendly and accessible from any device with internet access.

Method #2: Software Solutions

Software like Adobe Photoshop and GIMP support WebP and AVIF. For Photoshop, you might need a WebP plugin, while GIMP natively supports both formats. Simply open your image, go to “Export As” or “Save As,” and select WebP or AVIF from the format options.

Method #3: Command Line Tools

For a more technical approach, you can use command-line tools like cwebp for WebP and avifenc for AVIF. Install these tools via Homebrew on macOS or your package manager on Linux. 

How to Extend Support for AVIF and WebP as a Hosting Provider?

For WordPress hosts looking to stay ahead of the curve, extending support for AVIF and WebP is a game-changer. 

1. Ensure your server has the necessary libraries: libavif and libwebp. 

2. Update PHP to version 8.1 or higher and recompile the GD extension with AVIF support. Alternatively, you can configure PHP GD and ImageMagick.

This setup empowers your hosting service to handle these modern, optimized image formats seamlessly.

Want a hassle-free solution? 

Consider migrating to InstaWP Live, a white labeled hosting service that fully supports AVIF and WebP. This allows you to offer cutting-edge image optimization without the technical headaches. Plus, you get expert support, seamless integration, and advanced development tools. 

InstaWP Live takes care of the heavy lifting, so you can focus on growing your business.

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