It also takes the work of actually compressing the images off of your own server. This compression is lossless and won’t alter the quality of the images. The plugin does this by sending images files to the Optimus server and returning new, smaller versions to use on your site. If bandwidth is a concern, Optimus optimizes uploaded WordPress images up to 70%. Smush Pro ($6 per month) reduces file sizes more than the free version, and also removes file size limits (the free version restricts you to images under 1 MB). The free version of Smush and its paid companion, Smush Pro, are excellent all-around options for most WordPress users looking to compress their images but who don’t have time to compress each image themselves. Any new images you upload will be optimized automatically too as long as the plugin is installed.

Then, it will optimize all of your existing images. If you install this plugin on an existing site, all you need to do to turn it on is go to the plugin’s settings. It also takes other measures to improve page performance including lazy loading and auto-resizing. It applies lossless compression (meaning no quality is removed from the image file) to reduce your image size by up to 5 MB, individually or in bulk. Smush is the most popular image optimization plugin available for WordPress.

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