: The original free image compressor and optimizer plugin


The Image Optimizer is a free WordPress image compressor and optimizer plugin which allows you to smush your website’s images so that they load faster.
The plugin is super easy to use (just 2 clicks!), supports JPG, PNG and GIF image formats and can be used to bulk optimize current (past) images and automatically optimize all new images.
You can also adjust the optimization levels and exclude certain images.
Since its launch more than 9 years ago, has become the preferred choice for WordPress image optimization as it allows you to smush the images for free. image optimization service works on various CMS platforms (WordPress, Drupal, Joomla, Magento, Prestashop, etc.) and is used by more than 400,000 websites worldwide. has earned the reputation of being the best free, fast and easy image optimization plugin out there 🙂

– Free bulk image compressor
– Automatic image optimization on upload
– Keep or remove EXIF data
– Image quality selector
– Exclude images from optimization
– Powerful and free image optimizer API
– Customizable settings for image quality
– Automatic image optimization with CRON
– Backup and restore original images
– Image statistics
– File logging for developers


  • The simple interface


  1. Upload resmushit-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 !


How does Image Optimizer compare to other image optimization plugins (e.g. Smush, Imagify, TinyPNG, Kraken, EWWW, Optimole)? Image Optimizer offers advanced image optimization and provides many of the premium features you’ll find in competing services for free.
Plus, we’ve earned a reputation for being the best free, fast and easy image optimization plugin out there:-)

¿Cómo de bueno es

Al haber optimizado más de de imágenes, hemos desarrollado nuevas habilidades. Nuestro servicio aún está en desarrollo para ofrecerte nuevas locas funcionalidades.

¿Qué pasa con WebP y los formatos de imagen de próxima generación?

Estamos trabajando en una nueva oferta para ofrecerte lo mejor de estas nuevas características. Por favor, ten paciencia, llegará pronto 🙂

Is there a function «Optimize on upload»?

Absolutely, this function is activated for all newly added images and can be deactivated if desired.

Is there a CRON function?

Yes, you can optimize your images with cronjobs for large (and also for small) media libraries.

¿Puedo elegir un nivel de optimización?

Yes, by default the optimization level is set to 82. However, you can further optimize your images by reducing the optimization level.

Can I return to my original images?

Yes, by excluding/reverting an image, you will have your original image available again.

¿Es posible excluir algunas imágenes del optimizador?

Yes, since version 0.1.2, you can easily exclude an image from the optimizer.

Am I at risk of losing my existing images?

No! Image Optimizer creates a copy of the original images and performs optimizations only on the copies.

Is it free?

Yes ! Absolutely free, the only restriction is that the images must not be larger than 5 MB.

Where do I report security bugs found in this plugin?

Please report security bugs found in the source code of the Image Optimizer plugin through the Patchstack Vulnerability Disclosure Program. The Patchstack team will assist you with verification, CVE assignment, and notify the developers of this plugin.


2 de abril de 2024 1 respuesta
Works like a charm and its free??!! What is the catch here! 🙂 Thank you for the great work!
14 de marzo de 2024 1 respuesta
Sorry to bother you,there is a problem that bothers me. I want to use this plugin to compress images on my website, but my server's firewall blocked this operation. So I want to know the server IP address used by the compression process interface, then I can add to the whitelist. Thank u so mush! Best wishes
27 de julio de 2023
Very nice plugin for optimization!I propose to make support for converting images to WebP format.It would also be nice to increase the speed of image processing.Thank you!
19 de diciembre de 2022
This is a must have plugin i have installed on my websites. Thanks for such a great free tool! I will recommend this as one of the best image free optimizer.
Leer todas las 134 reseñas

Colaboradores y desarrolladores

« : The original free image compressor and optimizer plugin» es un software de código abierto. Las siguientes personas han colaborado con este plugin.


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Registro de cambios


Release date March 29, 2024
* Fix: The new image size after compressing/restoring the image is now saved correctly in WordPress;
* Tweak: Updated the settings page and added more support links and a «Rate Us» button;


Release date March 12, 2024
* Fix: A PHP Notice was displayed in the logs for certain settings;
* Tweak: Updated the settings page and added a «Support Us» button.


Release date February 22, 2024
* New: The plugin settings have been moved to the «Settings» menu and the layout has been updated;
* New: Added a Restore button next to each item in the Media Library;
* New: An improved logging mechanism has been added;
* New: The columns of the Media Library have been restructured and the layout and texts have been updated;
* New: A dedicated box has been added on the image edit screen, with all the plugin actions;
* Compat: The plugin is compatible and tested with PHP versions up to 8.3;
* Fix: The exclude function can now be used directly in the list view of the Media Library;
* Fix: The bulk restore function has been improved and should now work better;
* Fix: The wording of the plugin has been updated and the JS messages have been converted to translatable strings;
* Fix: The languages folder has been removed so that the plugin can be translated via the Translate WordPress project;
* Fix: The JS part has been updated to fix the deprecated jQuery JSON parser;
* Fix: The jQuery events are now associated with the «click» action instead of «mouseup»;
* Fix: The plugin actions of files that cannot be processed (PDF, SVG, etc.) have been removed;


  • Fix Optimize button in listing


  • Patreon new message


  • Patreon display message 🙁


  • Missing image


  • Partnership with Shortpixel
  • fix crash bug when uploading non Image document in library (while log enabled)


  • Compatibility with WP 6.1.0
  • Compatible with PHP 8.1.X
  • Fixed issue on Undefined array key «file» in …/resmushit.php on line 114


  • Incorrect library imported (fix PHP Fatal error: Uncaught Error: Undefined constant “SECURE_AUTH_COOKIE” in /wp-includes/pluggable.php:923)


  • Security fixes : CSRF protection for Ajax Calls


  • Security fixes : protection in a WP’s way


  • Security fixes : prevent XSS breachs


  • Avoid SSL verifications if certificate of remote endpoints fails.
  • Security fixes : escape POST, and admin user check for AJAX requests


  • Compatibility with WP 6.0.1
  • Security fix issues (
    • force int to ID in some SQL requests
    • check that user is connected as admin/contributor for AJAX actions
    • Message to indicate that there’s no collection of data in contacting remote feed service


  • Compatibility with PHP8+WP 5.8.2


  • Official support of WP-CLI
  • Fix cron context optimization


  • New option to restore all original pictures


  • Fix : Default value assignment
  • Test on WP 5.7.1


  • Fix : Optimize button not working when creating a new post
  • Fix : Default value of variables incorrectly initialized
  • Test on WP 5.5.1


  • hotfix : deprecated function used


  • Fix : OWASP & Security fix


  • Fix : Fix warning in variable not set (metadata)
  • Fix : Add an extension uppercase check


  • Fix : CSS+JS load on every admin page, now restricted to pages & medias
  • Fix : Links verification format for admin menu


  • Fix : cron multiple run issue.


  • Nueva imagen de cabecera, nueva descripción en WP para la página del plugin.


  • Problema en el número de la versión


  • Corregir el lanzamiento doble de la tarea programada. Añadido el tiempo de espera
  • Corregir el mensaje «Reducir a 0 (0 guardado)» si las estadísticas están desactivadas
  • Devolver un error si el archivo adjunto no se encuentra en el disco


  • Corregir la comprobación de la variable (generar un aviso)


  • Corregir escritura del registro (problema de permisos)
  • Corregir el error «Reducir a 0 (0 guardado)». Optimizar un solo adjunto mientras «Optimizar al subir» está desactivado


  • Añadir la opción de borrado de la copia de seguridad
  • Añadido un script para borrar copias de seguridad antiguas
  • Cambiada la inclusión de JS


  • Añadir la característica de mantener los datos Exif


  • Corregir el problema en la solicitud SQL para el prefijo de tabla diferente de `wp_`


  • Problema con el número de la versión


  • Corregir los ajustes reiniciados automáticamente.


  • Complete French translation
  • Plugin translation fix


  • Add CRON feature
  • Code refactoring
  • Fix issue for big Media library, with a limitation while fetching attachments
  • Fix log path issues


  • Add Settings link to Plugin page
  • Limit options to image attachments only
  • Fix RESMUSHIT_QLTY is not defined


  • Fix on attachment metadata incorrectly returned (will fix issues with other media libraries)


  • WordPress 5.0 compatibility


  • Fix PHP errors with PHP 7.2
  • Code refacto


  • Fix JS on «Optimize» button for a single picture
  • Provide a new «Force Optimization» for a single picture


  • Evitar los errores filesize () : stat failed si falta un archivo de imagen
  • Registro de comprobación de los permisos de los archivos
  • Comprobar las extensiones al subir (evitar usar la API de si no es una imagen)
  • Aumentar el tiempo de espera de la API para imágenes grandes (10 segundos)


  • Corregir el fallo (optimización que no funciona) en la subida en lotes cuando no está seleccionado «Optimizar al subir»
  • Nuevo banner en la cabecera por los 4 mil millones de imágenes optimizadas


  • Añadir una corrección para la compatibilidad con `allow_url_fopen`
  • Cargado el feed de noticias desde una URL SSL


  • Rotar el registro si el archivo es demasiado grande


  • Probado hasta WordPress 4.9.5
  • Nuevo colaborador (resmushit)
  • Completar la traducción


  • Probado hasta WordPress 4.9.1
  • Nuevo banner en la cabecera para los 3 mil millones de imágenes optimizadas 🙂


  • Probado hasta WordPress 4.8.1


  • New header banner for 2 billionth images optimized 🙂


  • Slovak translation fix


  • Slovak translation fix


  • Italian translation added (thanks to Cristian R.)
  • Description minor correction


  • Slovak translation added (thanks to Martin S.)


  • Bug fix when images uploaded > 5MB
  • List of files above 5MB
  • Translation minor corrections


  • Error management if webservice not reachable
  • Filesize limitation increased from 2MB to 5MB


  • CSS Fixes


  • Translation correction
  • News feed images correction


  • Borrar también el archivo original al borrar un adjunto
  • Exclusión de un adjunto de la optimización de (casillas de verificación)
  • Añadir la traducción al francés
  • Optimizaciones del código
  • 4.6.x check
  • Minor bugs corrections


  • Optimizar al subir
  • Estadísticas
  • Registro de servicios
  • Reconstrucción de la interfaz
  • Feed de noticias desde


  • base del plugin
  • optimizador en lotes