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Robin image optimizer — save money on image compression

Robin image optimizer — save money on image compression


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Make your website faster by reducing the weight of images. Our WordPress image optimizer plugin can cease image weights on 80% without any loss of quality.

Robin image optimizer is a smart and advanced image optimizer that really stands out among other WordPress plugins. Robin image optimizer is a WordPress free image optimizer plugin with zero limitations in terms of number of images and optimization quality. The only thing that you may stumble across is the image weight, which shouldn’t exceed 5 MB.

What’s the purpose of image optimization?

The lighter the weight of the image – the faster your page loads. With the constant growth of mobile users, increases the necessity in mobile websites optimization. If you don’t want to get many rejections and lose money due to the poor ad performances, we’d recommend you to start with image optimization.

Why should we use Robin image optimizer for image optimization?

  • The first and the most significant difference from the counterparts: our plugin is absolutely free and has the same features as paid products.
  • This WordPress image optimizer doesn’t have any limits or restrictions in image optimization.
  • Automatic optimization using Cron. You don’t need to wait til optimization is completed; the plugin will be optimizing couple of images every several minutes in the background.
  • Manual mass-optimization. Press the button and wait til your images are optimized
  • Image backup. Before optimization starts, all images are being stored in original quality. Then, when optimization is over, you can restore lost images or re-optimize them in another quality.
  • You can choose compression mode (normal, regular, high). Compression mode influences image weight and quality. The higher the compression, the worse is the quality and the smaller is the weight.
  • Image optimization on boot.
  • Reducing pre-optimization image weight by changing image size.
  • Detailed statistics on optimized images

WP CLI commands (PRO)


  • wp robin optimize
  • wp robin stop
  • wp robin status

Available scopes

  • media-library
  • custom-folders
  • nextgen


We invite you to check out a few other related free plugins that our team has also produced that you may find especially useful:

Thanks the authors of plugins

We used some useful functions from plugins Imagify Image Optimizer, Smush Image Compression and Optimization, EWWW Image Optimizer, reSmush.it Image Optimizer, ShortPixel Image Optimizer.


If you want to help with the translation, please contact me through this site or through the contacts inside the plugin.


  • The simple interface
  • Optimization log
  • Settings page
  • Media library


  1. Upload robin-image-optimizer to the /wp-content/plugins/ directory.
  2. Activate the plugin through the ‘Plugins’ menu in WordPress.
  3. All your new pictures will be automatically optimized !


Why is this plugin free and how long it will be this way?

Our WordPress plugin to optimize images uses API of this free service: https://resmush.it, So as long as these guys allow free image optimization, our plugin will remain free. Still, we have several ideas of how to make optimization free and planning to implement them in our plugin.

Are there any limits for image optimization?

There are no limits for image optimization in our plugin. The only thing we have is a kind of a restriction of image weight – it should be greater than 5 MB. But our plugin can reduce pre-optimization image weight, so you’ll be able to optimize almost all images you have.

What image formats do you support?

Robin image optimizer can optimize jpg, png and gif (both animated or not).

Do you remove EXIF images data?

EXIF-data is removed by default. However, you can keep it by disabling the feature.

Do you remove source images?

No. Robin image optimizer replaces images with their optimized analogues. The backup option stores source images and allows restoring them in one click.

Can I re-optimize images in another mode?

Yes. By enabling the backup feature in the plugin, you can re-optimize any image using another compression mode.

Does plugin support WebP format?

Yes, use modern image formats, such as WebP. Robin image optimizer PRO automatically creates WebP copies of your original images.

Browsers with the WebP format support will display WebP images. Other browsers will replace such images with JPG, PNP, GIF, BMP, etc.
Learn more about PRO version

Plugin has integration with Nextgen gallery?

Robin image optimizer PRO has full integration with NextGen Gallery, which helps to use all the plugin features.
Learn more about PRO version


Kasambula 8, 2024 1 reply
This optimises images very well with 3 levels available. It also has a great UI that puts a lot of paid-for options to shame. EDIT – This plugin is now a scam. I purchased the access to a premium server which until a few months ago was working fine. However, the premium server now no longer works and it seems that it has been turned off. I have sent messages both to the developer of this plugin AND the payment company they use (Freemius) and have received no reply. I am now contacting my bank to request a refund. DO NOT GIVE ANY MONEY TO THIS COMPANY!
Kasambula 17, 2023
This was my message to the support team. “On my website, a 500 error has occurred since updating to the premium version with the license key as provided. I started the premium version two nights ago because I want to convert my images to the webp format. The CLS on my site is too poor, and the images significantly contribute to this. Since the activation, the 500 error has been occurring. Simultaneously with each error message, the plugin throws an error and mentions the Robin Image Optimizer (see screenshot). I had made/changed the following settings: from server 1 to premium server (it was displayed that I have to select this), I have reactivated the auto-optimization at upload and activated convert to webp – specifically, replace image URLs (redirection was allegedly not possible), Resize large images and also changed from scheduled to background. I have now switched back to scheduled, but the problem has not been resolved. Since activation (more than 30 hours have passed), only 0.8% of 1315 images have been optimized. I have the feeling that something is not right with the settings because I have been using the Robin Image Optimizer in the free version for about 1.5 years. Please help me as soon as possible.” After five days, I unfortunately had to deactivate, delete and replace the plugin with another one. I am now using Imagify, which works great. I have deactivated the license for Robin Image Optimizer. I am really upset that I paid for the premium version – simply for nothing. And now I’m paying again for another plugin. This is unacceptable. (I used free version before without any problem).
Read all 114 reviews

Contributors & Developers

“Robin image optimizer — save money on image compression” is open source software. The following people have contributed to this plugin.


“Robin image optimizer — save money on image compression” has been translated into 4 locales. Thank you to the translators for their contributions.

Translate “Robin image optimizer — save money on image compression” into your language.

Interested in development?

Browse the code, check out the SVN repository, or subscribe to the development log by RSS.


1.6.6 (23.11.2023)

  • WordPress 6.4 Compatibility
  • Added: Compatibility with php 8.2

1.6.5 (27.05.2023)

  • WordPress 6.2 Compatibility
  • Added: Compatibility with php 8.1
  • Fixed: Minor bugs.


  • Fix for image optimization


  • WordPress 6.0 Compatibility


  • Errors fixes


  • Update modules and compatibility WP 5.8
  • Statistic fixes


  • Added: Separate conversion of the media library to WebP (PRO)
  • Fixed: Cancel background processing


  • Fixed: Error on frontend


  • Fixed: WP 4.8 compatibility


  • Added: Background image optimization on upload
  • Added: New logging system
  • Added: Output of the total number of images for optimization
  • Added: Russian translate
  • Added: (PRO) New optimization method: in the background.(This method works much faster, but it is still in beta and disabled by default. You can enable it in the settings.)
  • Added: (PRO) WP CLI commands
  • Deleted: Lazy Load options
  • Minor interface changes


  • Added: Subscribe form
  • Fixed: Potential rest api registration error
  • Added: Support for the WP Retina 2x plugin
  • Added: Badge with the date of the next quota update


  • Added: Lazy Load option for images


  • Fixed: jQuery.fn.load() and other bugs after update to WordPress 5.5


  • Fixed: Problem with choosing an optimization server on WordPress 5.5
  • Added: Optimization mode for Google PageSpeed [PRO]


  • Fixed: Unable to change the server if it is unavailable after selection.
  • Added: Added filter wbcr/rio/backup/backup_dir for changing the backup directory.
  • Added: Restriction of free servers (at the request of administrators of free servers)
  • Changed PRO feature: WebP conversion is not possible without using a premium server
  • Added: Ability to optimize files of selected formats (JPEG, PNG, GIF)
  • Added: Ability to choose the order of image optimization: starting with new images or starting with old ones

1.4.2 (21.01.2020)

  • Fixed: Сompatible with Clearfy 1.6.3.
  • Fixed: PHP error “Class ‘Wbcr_FactoryClearfy_Compatibility’ not found”.
  • Fixed: Minor bugs.
  • Removed: Server 4 beta.
  • Added: Premium server.

1.4.1 (24.12.2019)

  • Fixed: Some bugs
  • Added: Сompatible with WordPress 5.3


  • Fixed: Php warning (Declaration of WRIO_Image_Statistic_Folders)


  • Fixed: Plugin pages loaded for a very long time.
  • Fixed: Bugs with error logging.
  • Fixed: Error warnings have become more understandable.
  • Fixed: Мigration bugs with cache plugins.
  • Fixed: Bulk optimization stopped if an error occurred during image optimization.


  • Fixed: Minor errors


  • Fixed: PHP Error: Illegal mix of collations.
  • Fixed: Error 500 when trying to migrate.
  • Fixed: Context class not found error.
  • Fixed: PHP Fatal error: Class ‘WRIO_StatisticPage’ not found.
  • Fixed: Auto optimization on upload. Error in Gutenberg.
  • Fixed: Bug when restoring backup. Also increase the recovery quota for backup.
  • Added: Compatibility with WordPress 5.2.x
  • Updated: Improved error logging.


Fixed: On sites with php version 5.6 and below there was a syntax error.
Fixed: Broken links to support service.
Fixed: If site had a lot of images 15,000 and higher, bulk optimization page was loaded slow.


  • Added: Compatibility with WordPress 5.1.x
  • Added: Required php version 5.4
  • Added: Last optimization log. You can view latest optimized images, as well as monitor errors when optimizing images.
  • Added: New server optimization (Server 4). The server is free, at the moment it is in beta mode.
  • Added: Custom quality values. You can set your own image optimization quality settings.
  • Added: Resize images in height and width. Previously, plugin automatically resized largest image side.
  • Added: Select the optimization mode. Before you start optimizing, you will see a modal window, which will offer you 2 modes of optimization (scheduled and manual).
  • Added: Improved error debug. Now you can learn more about all the errors in optimizing images using the powerful debug log.
  • Added: Server rating. Now you can easily choose a server to optimize images based on its rating.
  • Added PRO feature: WebP Conversion. Use modern image formats, such as WebP. Robin image optimizer PRO automatically creates WebP copies of your original images. Browsers with the WebP format support will display WebP images. Other browsers will replace such images with JPG, PNP, GIF, BMP, etc.
  • Added PRO feature: NextGEN Gallery Integrations. Do you use a popular plugin to create galleries? Robin image optimizer PRO has full integration with NextGen Gallery, which helps to use all the plugin features.
  • Added PRO feature: Compress any Image in any Directory. Optimize images of themes and plugins! Robin image optimizer PRO can optimize images in any directory. If the themes & plugins developers don’t optimize their products Robin will fix it!


  • Fixed: Added compatibility with ithemes sync


  • Fixed: Compatibility with W3 total cache
  • Fixed: Compatibility with External Media without Import


  • Fixed: Some bugs
  • Fixed: Removed limit on image resizing
  • Fixed: Update core framework
  • Added: New free server
  • Added: Servers status, you can select available servers to optimize images
  • Added: Added compatibility with the plugin Clearfy
  • Preparing plugin for multisite support


  • Added: Ability to re-optimize images with errors.
  • Fixed: Some bugs
  • Added: An alternative server for image optimization. Now you can select an alternative optimization server if the current server is unavailable.
  • Fixed: Problems with translations

= 1.0.7
* Fixed: Images are saved in a size 0 bytes
* Fixed: Trying to backup file with empty filename
* Fixed: Curl replacement for file_get_contents
* Fixed: Statistics


  • Fixed: fixed bar progress styles
  • Fixed: changed the link to the reviews page


  • Fixed: corrected image size calculations for individual optimization


  • Fixed: update core framework


  • Fixed: small bugs


  • Release