WordPress 6.5, released in 2024, lets you upload and display AVIF images through the media uploader. No plugin required. The catch is your server. If its image library cannot decode AVIF, WordPress will not generate thumbnails or smaller sizes. That single gap trips up most shared-hosting setups. Here is how to check yours, what to do if it fails, and how to serve a fallback for the few visitors on browsers that cannot display AVIF.

Native AVIF Handling in WordPress 6.5

WordPress 6.5 accepts AVIF files through the standard media uploader. Add one to your collection and WordPress stores it, then serves it to visitors. Chrome, Firefox, Safari, and Edge all render AVIF. That covers most of your audience. No extra code needed.

The server is the bottleneck. WordPress relies on the host's image processor, either Imagick or GD, to create resized copies of every uploaded image. If that processor lacks AVIF capability, thumbnail and medium-sized versions never materialise. You end up serving the full original file, which is probably larger than you intended.

How to Check Your Server

Go to Tools → Site Health → Info → Media Handling. That panel names the active image processor and states whether it handles AVIF. The answer dictates everything that follows.

Server Requirements for AVIF Processing

Two libraries matter. Here is the split:

  • Imagick (ImageMagick) can process AVIF, but only if the installed version is recent and compiled with AVIF turned on. Most shared hosts ship an older build that omits it.
  • GD does not handle AVIF. At all. If your server runs GD, WordPress cannot create any resized versions of your AVIF uploads.

You can still upload AVIF files on a GD server. They just arrive as-is, with no thumbnails. The original gets served at its full dimensions, which may bloat page weight.

Check the Media Handling section under Site Health. If you see “GD” or an outdated Imagick, ask your host to update the image stack. Some providers will enable AVIF in Imagick on request.

Adding AVIF Images to Your Collection

Step by Step

The upload flow matches what you already do for a JPG or PNG.

  1. Open Media → Add New in the admin panel.
  2. Drag an AVIF file into the upload zone, or click “Select Files” and pick one.
  3. WordPress processes it. On a capable server, resized versions appear. On a GD host, only the original file lands.
  4. Insert the image into any post or page from the media picker.

WordPress 6.5 recognises the MIME type image/avif and handles it without extra configuration.

Fallback for Older Browsers

Every major current browser renders AVIF. A handful of older or niche ones do not. For those visitors, a missing image shows a broken icon. You can fix that.

Using the Picture Element

Convert your AVIF to a JPG before uploading. Keep the AVIF for quality. Upload both files. In your theme or via a plugin, wrap the image in a element that lists the AVIF source first and the JPG second. Browsers that understand AVIF load it. The rest fall back to the JPG.

Managing two files per image is more work. The alternative: convert everything to AVIF, upload only that, and accept that a small slice of visitors will see a broken image icon or alt text. The trade-off is real but the affected group is tiny.

Converting before upload gives you control over quality and file size. From there, decide whether the JPG fallback is worth the upkeep.

Managing AVIF Files in Your Collection

WordPress treats AVIF files like any other image. You can search for them, edit titles and alt text, and drop them into posts. The friction appears when your server cannot process AVIF. In the grid view, you see a generic file icon instead of a thumbnail. Front-end display still works. Back-end browsing gets harder.

If you need thumbnail previews and your host runs GD, convert images to AVIF before uploading, then use a plugin that generates previews with client-side JavaScript or an external processor. Another path: upload a matching JPG for each AVIF. Let the JPG handle the preview. Serve the AVIF on the front end.

Checking Your Server’s Image Processor

Here is the quick audit:

  1. Log in to the WordPress admin.
  2. Navigate to Tools → Site Health.
  3. Click the Info tab.
  4. Scroll to Media Handling.
  5. Find the line labelled “Image library” or “Image editor”. It reads either “Imagick” or “GD”.

If it says “Imagick”, your server might handle AVIF. Upload a test file and check whether resized copies appear. If it says “GD”, you have no server-side AVIF processing. Rely on the original file alone or ask your host to upgrade.

Choosing AVIF as Your Format

AVIF delivers smaller files and better fidelity than JPG at the same visual quality. The decision comes down to two factors: your host’s image processor and browser coverage. For most site owners, the benefits win. Modern browsers already render AVIF, converting before upload keeps quality in your hands, and a fallback catches the stragglers. Need a converter? avif.tools offers a free, watermark-free tool.