There are all kinds of WordPress Image optimizer plugins available in the WordPress plugin repository. They can help you compress images for the web or handle things like resizing images or lazy loading.

In this post, we’re going to look at the features of the most popular image optimization plugins. Some are all-in-one image optimizers while others have some unique strengths that make them helpful additions, but all of them will help you serve up images on your site much faster.

  • Smush

    I don’t want to brag, but Smush is the most popular free image optimization plugin for a reason. It’s the best WordPress image optimizer because it is an all-in-one solution that has lossless image compression, lazy loading, bulk smushing (so you can optimize up to 50 images at once) and more. With over 1 million active installations, Smush has optimized literally billions of images.

    Smush will process PNGs, JPEGS and GIFs on OUR superfast servers, freeing up resources on your server so your site performance will not be affected. And the best part? The free version has no daily, monthly or annual caps so you can optimize to your heart’s content. As long as your images are under 5MB we’ll Smush it.

    If you want even more cool features, then Smush Pro, with her lightning fast CDN, can help you resize images, convert images to WebP, automatically resize your images, convert PNGs to JPEGs, compress images in other directories or in your Amazon S3 cloud and more.

    Plus, Smush and Smush Pro integrate well with other popular image plugins such as NextGEN Gallery, WP Offload S3 and WP Retina 2x. Try Smush Pro free for 30 days to see how she can take your site performance to new levels.

  • EWWW Image Optimizer

    EWWW Image Optimizer automatically and losslessly optimizes your images as you upload them to your site. It can also optimize images that you have previously uploaded.

    Another nice feature of this plugin is the ability to convert your images to the file format that produces the smallest image size. It can also optionally apply lossy reductions for PNG images.

    The plugin is free if you use your own servers to optimize your images. Something to be aware of is if you can’t use the exec() function on your server, you’ll have to pay to use the EWWW I.O. API. If you opt to use the EWWW service, you’ll have to pay an additional fee.

    Interested in EWWW Image Optimizer?

  • Imsanity

    Don’t be scared off by Imsanity’s freaky feature image in the WordPress Plugin Repository. This free image optimizer plugin automatically resizes images to a more “sane” size by using WordPress’ built-in image scaling functions.

    A nice feature of Imsanity is the ability to set a maximum width, height and quality. You can also convert BMP files to JPG so images can be scaled.

    With Imsanity, you’ll be able to bulk resize images. When Imsanity scales an image, it replaces the original image.

  • Imagify Image Optimizer

    Another image optimizer plugin is WP Media’s Imagify Image Optimizer that automatically optimizes an image when it is uploaded into WordPress. It also has the ability to bulk optimize images.

    Imagify Image Optimizer will optimize your images in WordPress by resizing images. It also has three levels of image compression and the ability to convert your images to WebP.

    Imagify Image Optimizer is compatible wtih WooCommerce and NextGEN gallery.

    You’ll be able to optimize up to 25MB of images which is about 250 images every month. Keep in mind that WordPress generates multiple additional images for every single image you upload, so this will count toward your limit. Once you pass your limit you’ll need to upgrade to a paid plan.

    Interested in Imagify Image Optimizer?

  • Compress JPEG & PNG images

    Compress JPEG & PNG images integrates with the popular WordPress image compression services TinyJPEG and TinyPNG.

    With Compress JPEG & PNG images, your images will automatically be optimized when uploaded. You can also optimize images that are already in your media library, one at a time or in bulk.

    Compress JPEG & PNG images has encoding for progressive JPEGs, and is the best compressor plugin for animated PNGs. It is compatible with WP Retina 2x, WP Offload S3, WooCommerce (although there are a few known issues) and is WPML as well as multisite compatible.

    There are no file size limits but if you want to optimize more than 100 images a month, you’ll have to upgrade to a paid account. Again, keep in mind that when you upload one image, WordPress generates additional sizes to make your site responsive, so those additional images will count toward your limit.

    Interested in Compress JPEG & PNG images?

  • ShortPixel Image Optimizer

    ShortPixel Image Optimizer is not only for images, but it’s a PDF optimizer that’s free. As with the other WordPress image optimization plugins, new images are automatically resized and optimized when you upload.

    ShortPixel Image Optimizer is great at compressing images for your website because it has both lossy and lossless image compression for for JPEGs, PNGs, WebPs, GIFs and PDF files. It also has a free image compressor called glossy image compression that was designed as a photo optimizer setting for photographers that preserves the quality of an image.

    ShortPixel is GDPR compliant and integrates well with NextGEN gallery, Foo Gallery and any other galleries and sliders.

    ShortPixel comes with 100 free credits/month and additional credits can be bought for as little as $4.99 for 5,000 image credits.

    Interested in ShortPixel Image Optimizer?

  • WP Retina 2x

    WP Retina 2x is not an image optimizer for WordPress like the other plugins on this list. It is in a class of its own.

    WP Retina 2x is used for serving Retina images on your WordPress site. Retina images are tremendously resource intensive because they’re twice as large as normal images, so you need a plugin that will help you serve them properly.

    See our post on how to serve Retina images in WordPress without slowing down your site for a detailed tutorial on how to configure WP Retina 2x.

    We’ve mentioned how some of the other plugin on this list pair well with WP Retina 2x in order to optimize your images in WordPress while still making sure that your images are high quality so they look good on Retina screens.

    Interested in WP Retina 2x?

  • reSmush.it Image Optimizer

    reSmush.it allows you to use the the free image optimization reSmush.it API. The API accepts JPEGs, PNGs and GIF files that are up to 5MB. The plugin is free to use with the only restriction being that your images need to be under 5MB.

    reSmush.it is not only an image optimizer for WordPress, but its API is also flexible enough to use with other CMS systems, such as Drupal, Joomla and Magento. So even though it has fewer installs compared to some of the others on this list, reSmush.it has smushed billions of images.

    reSmush.it sets the default optimization level to 92, but you can adjust this if necessary. You’ll also be able to specify if images should be optimized on upload.

    Interested in reSmush.it Image Optimizer?

  • Lazy Load

    Let’s not leave lazy load plugins off this list. Lazy load doesn’t need configuring because it is a simple and light plugin that works out-of-the-box.

    It uses jQuery.sonar to only load an image when it’s visible above fold. This plugin is an amalgamation of code written by the WordPress.com VIP team at Automattic, the TechCrunch 2011 Redesign team, and Jake Goldman from WordPress consultancy 10up.

    Lazy loading is an easy way to load your images more efficiently so your initial site loads more quickly.

    We recently added lazy loading to Smush. Learn more about how to lazy load images in WordPress.

  • Optimus Image Optimizer

    Last but not least on our WordPress optimization plugin list is Optimus. It automatically reduces the file size of uploaded images by compressing the images for your website.

    There is a free level that allows a maximum file size of 100kb. The free version does not include WebP conversion, but it does allow an unlimited number of images. Rather than using your server for WordPress, Optimus sends your images to the Optimus server in Germany for optimization, then sends it back once the image has been optimized.

    You will be able to specify if you would like Optimus to keep or remove the image metadata such as the author, EXIF and copyright information, for additional file size reduction.

    Optimus has a bulk image compressor, is compatible with WooCommerce, WP Retina 2x and WPMU, and does not store your images on their server once it is optimized.

    Interested in Optimus Image Optimizer?

Image Optimization Summary

While there are a lot of image optimization plugins available in the WordPress plugin repository, in our opinion Smush is the best image optimizer for WordPress because you do not have to upgrade to a paid account. With Smush you get a free image compressor and an auto-optimization plugin that streamlines your images on upload.

For even more features and faster smushing, Smush Pro can’t be beat. Try Smush Pro free for 30 days to see for yourself how it stacks up against these other WordPress Image Optimization plugins.

And while you’re at it, check out our ultimate guide to image optimization.