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AJAX Thumbnail Rebuild

By junkcoder

Site Administration & Utilities / Site Health & Diagnostics

Reviewed by Omar Dabbas

Trusted WordPress expert with 20+ years of experience evaluating plugins for the WP ecosystem.

AJAX Thumbnail Rebuild Review - In-Depth Analysis

AJAX Thumbnail Rebuild allows you to rebuild thumbnails on your site without server script timeouts. It processes thumbnails one at a time, making it suitable for sites with many images.

Performance Overview

WPS Score

6.81/10

User Rating

4.8/5 (based on 90+ reviews)

Active Installations

30,000+

Update Frequency

Below Average It is calculated using the weighted average of same category plugins.

Security Score

1 / 10 (Very Low Risk) It is calculated using the weighted average of all versions.

What It Does

AJAX Thumbnail Rebuild allows you to rebuild all thumbnails on your site. There are already some plugins available for this, but they have one thing in common: All thumbnails are rebuilt in a single step. This works fine when you don’t have that many photos on your site. When you have a lot of full-size photos, the script on the server side takes a long time to run. Unfortunately the time a script is allowed to run is limited, which sets an upper limit to the number of thumbnails you can regenerate. This number depends on the server configuration and the computing power your server has available. When you get over this limit, you won’t be able to rebuild your thumbnails.

Why would you want to rebuild your thumbnails? WordPress allows you to change the size of thumbnails. This way, you can make the size of thumbnails fit the design of your website. When you change the size to fit for a new theme, all future photos you are going to upload will have this new size. Your old thumbnails won’t be resized. That’s where this plugin comes into action. After changing the image sizes, you can rebuild all thumbnails. But instead of telling the server to recreate all thumbnails at once, they are rebuilt one after another. Rebuilding thumbnails for one photo won’t take all too long, so you won’t run into any script timeouts. Note that you still have to wait until all thumbnails have been rebuilt. If you close the page before the task is completed, you have to start all over again.

You can also select the thumbnail sizes you want to rebuild, so that you don't need to recreate all images if you've just changed one thumbnail-size. You can also choose to only rebuild post thumbnails (featured images).

This plugin requires JavaScript to be enabled.

Comparing to Alternatives

AJAX Thumbnail Rebuild stands out among several alternatives for regenerating thumbnails, offering unique features and performance benefits.

Top alternatives

Strengths

Efficiently regenerates thumbnails even for large image libraries
Automates thumbnail rebuilding process
Highly rated for ease of use and reliability
Performs tasks that some alternatives cannot
No known security vulnerabilities

Weaknesses

Lack of recent updates raises concerns about ongoing maintenance
Limited or no official support response
No pro version with additional features
May be flagged as abandoned by security tools

User Sentiment Analysis

With a high overall rating of 4.8 out of 5 from 90 reviews, users generally praise the plugin's effectiveness and ease of use, though a small minority express concerns about support and maintenance.

Positive highlights

"Nice plugin, very useful, efficiency top." — Wabbitt83
"It did what Regenerate Thumbnails can't." — Fred
"This is a great plugin, easy to use and it should be in Core." — Jasper
"This takes care of it in a couple hours without taking a break." — cr8n

Common complaints

No replies to support queries for over a year, suggesting abandonment

Weaknesses

Lack of recent updates
No active support
Potential abandonment concerns

Who Should Use This?

Best for

Users needing a reliable and efficient thumbnail regeneration tool for large image libraries who prioritize functionality over active support.

Not ideal for

Users who require active support, frequent updates, or a plugin with a paid premium version offering additional features.

Pricing & Value

Free version includes

The free version offers full functionality for regenerating thumbnails efficiently without limitations.

Final Verdict

AJAX Thumbnail Rebuild is a highly effective and efficient plugin for regenerating thumbnails, especially suited for users managing large media libraries. Its strong positive reviews highlight its ease of use and capability, outperforming some alternatives in specific scenarios. However, the lack of recent updates and limited support may be a concern for those seeking long-term maintenance and assistance.

Overall, this plugin offers excellent value as a free tool with no known security issues, but users should weigh the benefits against the potential risks of using a plugin that appears to be no longer actively maintained. Alternatives with active development might be preferable for those needing ongoing support.

Other Notable Features

Here are a few other notable features of this free AJAX Thumbnail Rebuild plugin.

ajax

thumbnail rebuild

regenerate thumbnails

Screenshots

FAQ

No. A rebuild writes the resized copies again and leaves the file you uploaded as it is. The only setting that touches an original is “Also optimise the full size original” on the Optimising tab, and even then only the lossless programs run on it – never a re-encode.

Yes, with one line of code. The screen has a single switch per format, but a filter separates the two, so the copies go on being written while the front end serves your originals – which is what you want when a CDN or the server itself hands the copies out:

add_filter( 'ajax_thumbnail_rebuild_serve_copies', '__return_false' );

An ACF image field hands back an array of every size the site registers, which is what it does unless you tell it otherwise – and to build that array it asks for all of them at once. With sizes waiting to be cut, that is a listing rather than a page asking to show a picture, and cutting ninety files inside a visitor’s page view to answer it is worse than the upload this feature was meant to spare you.

So nothing is cut while an ACF field is being read. The sizes already on disk are reported as usual; one that is still waiting is reported as the full file, which is what WordPress itself falls back to for a size that does not exist yet. Nothing else changes: the first time a template actually renders that size it is cut, exactly as before.

If you read sizes out of that array – $image['sizes']['my-size'] – ask the field for an ID instead and let WordPress draw the image:

'return_format' => 'id' on the field, then `wp_get_attachment_image( $id, 'my-size' )`.

To have it behave as it did before, cutting every size the moment such a field is read:

add_filter( 'ajax_thumbnail_rebuild_on_demand_while_enumerating', '__return_true' );

Contributors and developers

“AJAX Thumbnail Rebuild” is open source software. The following people have contributed to this plugin.

junkcoder

Risto Niinemets

Free Version Docs

WPS

6.81

Average

Ratings

4.8 out of 5 | 90

Version

2.2.1

Last updated

1 month ago

Active installations

30,000+

WordPress version

7.1.3 or higher

PHP version

7.4 or higher

Languages

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AJAX Thumbnail Rebuild Review - In-Depth Analysis

Performance Overview

What It Does

Comparing to Alternatives

User Sentiment Analysis

Who Should Use This?

Pricing & Value

Final Verdict

Other Notable Features

Screenshots

FAQ

Contributors and developers

Ratings

Reviews (90)

Sort by:

Contributors & Developers

Interested in development?

Changelog

Security Status

Secure

No Unpatched Vulnerabilities

Known Vulnerabilities (0)

Previous Versions

WPS

6.81

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