This plugin hasn’t been tested with the latest 3 major releases of WordPress. It may no longer be maintained or supported and may have compatibility issues when used with more recent versions of WordPress.



Attention: has been discontinued and this plugin is no longer maintained. See The future of responsive-io. is a service that optimizes and delivers perfect images for every screen.

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The plugin will make sure your tags are ready and that our javascript is loaded. All that unobtrusively without changing the content in your database.


  • Images are automatically resized to fit any device.
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  • We use WebP, progressive JPG and clever optimizations to make your images smaller.
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This plugin supports the GitHub Updater plugin, so if you install that, this plugin becomes automatically updateable direct from GitHub. Any submission to repo will make this redundant.


Using The WordPress Dashboard

  1. Navigate to the ‘Add New’ in the plugins dashboard
  2. Search for ‘responsive-io’
  3. Click ‘Install Now’
  4. Activate the plugin on the Plugin dashboard

Uploading in WordPress Dashboard

  1. Navigate to the ‘Add New’ in the plugins dashboard
  2. Navigate to the ‘Upload’ area
  3. Select from your computer
  4. Click ‘Install Now’
  5. Activate the plugin in the Plugin dashboard

Using FTP

  1. Download
  2. Extract the responsive-io directory to your computer
  3. Upload the responsive-io directory to the /wp-content/plugins/ directory
  4. Activate the plugin in the Plugin dashboard


How does it work?

It relies on WordPress “the_content” filter to change the images before handing over the output to the browser.

Contributors & Developers

“responsive-io” is open source software. The following people have contributed to this plugin.


Translate “responsive-io” into your language.

Interested in development?

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



  • Bug fix: Skipping GIFs as the service does not support that yet.


  • Bug fix: Using SmartDomDocument to avoid encoding issues.


  • Bug fix: removing acf filter to avoid charset conflicts.


  • Adding fallback script check. The fallback script will added to the queue and load in case the CDN fails.


  • Bug fix version. Making sure the scripts loads at the footer.


  • Bug fix version. Lower the priority to further avoid other filters conflicts.


  • Initial version. Changes images and check for [caption] to avoid conflicts.