Unlimited free image compression and WebP conversion, done instantly as you upload them. No quotas, no external servers, no limits.
As of April 2026, Cimo is a WordPress webp plugin with 6.0K+ active installations and a 4.8/5 rating from 12 reviews. It has been downloaded 25K+ times in total. Requires WordPress 6.7.5+ and PHP 8.0+. Available on WordPress.org since 2025. Actively maintained — updated within the last month. Downloads are up 483% this week. Support resolution rate: 100%. Top alternative: EWWW Image Optimizer.
Optimize all your images instantly and for free.
Cimo is a game-changer for media optimization. It optimizes, resizes, and converts your images instantly as you upload — even before the files are added to your Media Library.
Visit Cimo’s website to learn more about how Cimo does things.
From WordPress’ point of view, it’s as if you optimized your image BEFORE your uploaded it. Now, this is next-next-gen image optimization.
Cimo works like magic, drag your large image file, and an optimized image will automatically appear in your Media Library. This ensures your website load speed is perfectly optimized by keeping image sizes minimal, without compromising quality.
I really like this plugin. Set and forget! Limited options in the free version, but most of the time this is perfect.
Awesome plugin, directly goes to my default install list ! Thank you for the great work !
used to work perfectly. I wish I could find older versions, as 1.2.2 no longer automatically converts images when uploaded. never should have updated. so annoying, and now looking for a new solution.
update after dev response: I updated to 1.2.2 on other sites, and all have broken functionality. Will revisit this review after the next update.
Update after the update: I had to roll back to 1.2.0, and you can find that here in a dropdown menu at the bottom of the content area: https://wordpress.org/plugins/cimo-image-optimizer/advanced/
Cimo converts all images that are uploaded. That includes PNG-Files wich you may need for the favicon / site icon. There appears to be no way to avoid except for disabling Cimo. 🙁
I uploaded 5 images between 6 MB and 20 MB in less than 3 seconds. And the plugin works perfectly with Image Regenerate & Select Crop. All my custom image styles were cleanly applied and compressed to a minimal file size, and the whole thing is crystal clear. Thanks for your development. Fantastic work!
| WordPress | 6.7.5+ requiredTested up to 6.9.4 |
| PHP | 8.0+ required |
Plugin data sourced from WordPress.org. Analysis and metrics by PluginSift.