Regenerate Thumbnails

74 Quality Score

Active Installs

27/30

With 1,000,000 active installs, this is one of the most widely used image utilities in the WordPress ecosystem, which is the strongest signal of practical value here.

Update Freshness

15/25

The plugin was updated 2025-08-20 and is tested against WordPress 6.8.5, though the PHP 5.2.4 minimum requirement is dated and signals an older codebase rather than modern PHP support.

User Rating

14/15

A 92 out of 100 from 395 reviewers is a high score, indicating the users who actually rate it are happy with how it works.

Support Health

8/15

Support health is a weak point: 0 support threads listed in the tracker, which is common for this plugin because it is considered a finished utility, but it means there is no public help channel to fall back on.

WP Compatibility

11/15

Compatibility scores 75 because it supports back to WordPress 4.7 but the PHP 5.2.4 floor and lack of modern block editor integration keep it from scoring higher.

Scores higher than 35% of indexed plugins

About

Regenerate the thumbnails for one or more of your image uploads. Useful when changing their sizes or your theme.

Active Installs 1M+

Rating ★★★★½ 4.6/5

Last Updated 2025-08-20 3:56pm GMT

Requires WordPress 4.7+

Tested Up To 6.8.8

Requires PHP 5.2.4+

✓ No known vulnerabilities

What It Does

Regenerate Thumbnails rebuilds the cropped image sizes for every image in your Media Library based on the sizes currently registered by your theme and WordPress core. You can regenerate a single image, a batch of images, or your entire library through a dedicated admin screen. It is the standard tool for catching up on missing or outdated thumbnail sizes after a theme switch.

Who It's For

Anyone switching WordPress themes, adding a new image size to functions.php, or installing a plugin that registers its own image sizes will need this to refresh their existing media library. It is also useful for photographers, ecommerce stores, real estate sites, and magazine-style publications that change aspect ratios and need older images to match new layouts.

Who Should Skip It

If your site only has a handful of images or you are starting fresh with no existing Media Library, the manual re-upload approach is faster than installing a plugin. Sites on managed hosts with aggressive cron and memory limits may also run into trouble regenerating thousands of images in one pass.

The Bottom Line

For its narrow purpose, Regenerate Thumbnails is the default choice: 1 million installs, a 92 user rating, and recent testing on WordPress 6.8.5 make it a safe, boring, reliable utility. The main weaknesses are the dated PHP 5.2.4 requirement and the absence of a public support channel, so if you need retina support, WebP conversion, or cleanup of old files, look at Perfect Images or Force Regenerate Thumbnails instead.

Related Plugins

Force Regenerate Thumbnails 85/100

Pick this if you want to also delete old, unused thumbnail files from the server while regenerating, which saves disk space on large libraries.

Recent Posts Widget With Thumbnails 84/100

Choose this if your real goal is displaying recent posts with thumbnails in a sidebar widget, since Regenerate Thumbnails does not handle widgets at all.

Perfect Images: Regenerate Thumbnails, Image Sizes, WebP & AVIF 83/100

Choose this if you also need retina image support, WebP or AVIF conversion, and control over which custom image sizes get generated.

Quick Featured Images 83/100

Pick this if your primary problem is setting, replacing, or bulk-assigning featured images rather than regenerating the existing thumbnail files.

Conditionally display featured image on singular posts and pages

This is not a thumbnail regeneration tool, so only consider it as a complement if you also need to control where featured images appear on individual posts.