WordPress 7.1 "Mary Lou" — Image Formats and Speed Finally Get Real

wordpress performance avif images release

WordPress 7.1, code-named after jazz pianist Mary Lou Williams, is out. The release is packed with editor improvements — responsive styles without custom CSS, an admin bar in every editor, inline Notes with mentions, and new Playlist and Tabs blocks. But for anyone who runs WordPress sites, the two most interesting changes are about image formats and speed.

Native AVIF and HEIC support

WordPress 7.1 adds native support for AVIF, HEIC, and HDR gain maps. Modern cameras and phones already produce these formats — WordPress just never let you upload them directly. Now it does.

For anyone who has been converting images to AVIF manually (yes, us included — our blog covers have been AVIF for weeks), this removes an entire manual step. Upload the modern format, serve the modern format.

Image processing moves to the browser

The bigger news is how images get processed now. Compression, resizing, and thumbnail generation run in the browser, via a WebAssembly build of libvips.

What this means for servers:

  • No more PHP memory limits hit during uploads — the heavy lifting happens client-side
  • No more upload timeouts on large files
  • Smaller files produced than server-side processing
  • Server CPU offloaded — image work no longer competes with page rendering

For shared hosting and small VPS boxes — the exact scenario where WordPress struggles — this is a meaningful shift. Image processing is one of the most memory-hungry operations WordPress does. Moving it off the server is a genuine architectural improvement.

GIF-to-video conversion (opt-in)

GIFs are wildly inefficient — often 10-100x larger than an equivalent video. 7.1 adds opt-in GIF-to-video conversion, producing typically smaller files with the same visual result.

Why this matters for WordPress hosts

We've been debugging WordPress memory issues on a 2 GB VPS lately — opcache tuning, FPM limits, the works. Image uploads were exactly the kind of operation that could spike memory usage and trigger OOM kills. Moving image processing to the browser removes that whole class of problems.

Add speculative loading defaults configurable via environment variables, and WordPress 7.1 quietly becomes the most performance-conscious release in years.

The editor improvements are nice. The image pipeline changes are the ones that will keep your server alive.

Source: WordPress.org News, August 19, 2026.