Cimo – Free Instant Image Optimizer & WebP Converter

80 Quality Score

Active Installs

18/30

With 8,000 active installs, Cimo is a small player compared to EWWW Image Optimizer's one million installs, so its user base is still relatively niche but it recently grew enough to earn a popularity bonus above its baseline.

Update Freshness

25/25

The plugin was updated within the last few days of the data snapshot and requires PHP 8.0 and WordPress 7.0, signalling that the developer is actively shipping against current stacks.

User Rating

15/15

Twelve users have rated Cimo 96 out of 100, which is exceptional, though the small sample size means the score could shift quickly once more users review it.

Support Health

8/15

Only one public support thread exists and it was resolved, which is a 100% resolution rate but also means there is too little data to draw firm conclusions about long-term support responsiveness.

WP Compatibility

15/15

The compatibility score is at the maximum because Cimo declares support for the latest WordPress 7.0 release and PHP 8.0 with no older dependencies dragging it down.

Scores higher than 79% of indexed plugins

About

Unlimited free image compression and WebP conversion, done instantly as you upload them. No quotas, no external servers, no limits.

Active Installs 10k+

Rating ★★★★½ 4.9/5

Last Updated 2026-08-12 11:14am GMT

Requires WordPress 7.0.3+

Tested Up To 7.0.4

Requires PHP 8.0+

✓ No known vulnerabilities

What It Does

Cimo compresses images and converts them to WebP the moment you upload them to the WordPress Media Library, handling everything locally on your own server so no files are sent to third-party APIs. There are no monthly quotas, no account signup, and no per-image fees, making image optimization effectively free regardless of how many uploads your site processes. The plugin runs the conversion and compression automatically on upload, so existing media already in the library needs a separate bulk action to be processed.

Who It's For

This plugin fits sites that push a high volume of images through WordPress and want to avoid paying for SaaS image optimization services such as ShortPixel or Imagify. Photographers, stock photo libraries, news outlets, and e-commerce stores with constantly refreshed product galleries will get the most value, particularly those on tight budgets. Small sites with only a handful of images a month will see less benefit since the savings are smaller in absolute terms.

Who Should Skip It

If you only upload a few images per month, a free desktop tool like Squoosh or a single TinyPNG pass is faster than installing and configuring any plugin. Sites on very low-spec shared hosting should also skip this, because local compression and WebP conversion are CPU-heavy and will compete with your real visitors for server resources.

The Bottom Line

Cimo delivers an honest free-tier image optimizer with no quotas, near-perfect ratings, and a developer who is clearly active, but its 8,000 installs and single support thread mean you are an early adopter of a less proven option. The 79.38 overall score and strong maintenance signals make it worth trying on a staging site first, especially if you are tired of paying monthly fees to competitors. Once it crosses 50,000 installs with a wider rating base, the picture should be much clearer.

Related Plugins

EWWW Image Optimizer 89/100

Pick EWWW if you need a battle-tested plugin with a million installs, CDN-backed optimization for slow servers, and a more mature bulk conversion workflow.

Converter for Media 88/100

Pick Converter for Media when WebP and AVIF output are the priority and you specifically want the same local conversion approach used by over 500,000 sites.

Imsanity 86/100

Pick Imsanity if your real problem is oversized uploads being saved to disk rather than recompressing existing images, since it focuses on resize-on-upload rather than format conversion.