WordPress image optimisation plugins compared

What image optimisation plugins do

An image plugin runs after you upload (or on demand) and recompresses your media files, then serves the smaller result to visitors. Beyond raw compression, the features that differ between plugins matter more than the brand:

• Recompression. Lossy and lossless passes, and whether it keeps a backup of your original.
• Format conversion. Generating WebP or AVIF copies next to the original JPEG/PNG and switching the <img> source at render time.
• Resizing. Downscaling oversized originals (a 5000 px upload into a 1500 px hero) before compressed versions are made.
• Bulk and automation. Offloading the whole library, or only new uploads, with a throttle setting.
• Lazy loading. Deferring off-screen images so the browser does not fetch them until they scroll into view, which trims initial page weight.
• Offloading. Sending files to a CDN or cloud storage and serving URL rewrites, which changes the origin path.
• EXIF / metadata. Removing privacy data from images.

The image optimisation guide explains the format decisions; this page maps those decisions to WordPress plugin behaviour.

How the common plugins feel in practice

Details and prices change constantly, so treat the plugin names below as categories with typical behaviors, and verify a plugin's current feature list before choosing.

Two practical rules when reading the comparison:

• The mechanism matters more than the brand. A plugin that compresses through its own CDN differs from one that just wraps local conversion tools; the latter works offline, the former fails without network access. For a small site, the offline converter plus a rewrite rule is transparent and has zero recurring cost.
• WebP and AVIF are not the same. A plugin advertising WebP tells you about format, not about what it does with your original. Ask what happens to the master: kept or replaced. Keeping it means you can re-export later; replacing it means restore from the backup becomes your only path back.

Pick one, do not stack

The single most common WordPress mistake is running two image plugins at once. Two compression plugins with auto-on upload aggressively double-process every upload, and if one writes a WebP cache and the other writes separate derivatives, you get two optimized copies plus wasted CPU. Stick to one plugin per job:

• If you only need the format conversion + compression, one converter plugin is enough.
• If you also need offloading, choose a plugin whose offload is born in the same codebase rather than a second plugin.
• If you add a CDN image service, drop the plugin entirely; one technology owns the format and compression.

Choosing for your situation

• You have a small photo site: pick one local plugin with a quality ceiling and batch mode, run the batch over the existing library, then set auto on new uploads.
• You need WebP and AVIF and want CDN delivery: CDN image services were built for this, one pipeline, no origin CPU cost.
• You care about pixel-exact control: local tools with explicit quality and resizing options match your design system.
• You already use an image CDN: no plugin needed, the CDN handles format and compression at the edge.

Minimum setup regardless of plugin

1. Set a quality target (standard guidance is roughly 75 to 85 for photos, visibly loss-free).
2. Enable WebP and AVIF for the same library, or use the plugin's CDN mode.
3. Confirm upload_max_filesize and worker time handle the batch, as described in the media library upload fix.
4. Measure before and after with core-web-vitals, because a compression win shows up in LCP and page weight within the hour.

Caveats

• "Lossless" recompression is real but tiny; the big wins come from lossy quality and format conversion.
• Plugin pricing drifts. The credit, size, or offload pricing changes without notice; print the page you are deciding on.
• Nothing here is an endorsement of any single plugin's behavior; the features that match your library (offloading, EXIF handling, concurrency) decide the fit, and the table above describes typical behavior only.