Images can improve the experience on your site, elevate your brand, and provide additional assets to use in promotion. However, unnecessarily large images can increase page load speeds, which negatively impacts your SEO and causes frustration for your visitors.
You can mitigate these issues and enjoy all the benefits images have to offer by optimizing your images.
This is done by reducing image size and the way your site handles image loading. The process can be time-consuming if done manually, but WordPress users can take advantage of image optimizer WordPress plugins to streamline their efforts.
1. Smush
Smush is the most popular image optimization plugin available for WordPress. 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. It also takes other measures to improve page performance including lazy loading and auto-resizing.
Smush is an easy plugin for beginners. 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. Then, it will optimize all of your existing images. Any new images you upload will be optimized automatically too as long as the plugin is installed.
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. 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).
2. Optimus
If bandwidth is a concern, Optimus optimizes uploaded WordPress images up to 70%. The plugin does this by sending images files to the Optimus server and returning new, smaller versions to use on your site. This compression is lossless and won’t alter the quality of the images. It also takes the work of actually compressing the images off of your own server.
Optimus is a hands-off tool — it automatically processes the images as they are uploaded to your WordPress site, thus improving your site’s page performance without effort on your part. You have the option to stop the automatic optimization if you wish.
In addition to the free version, Optimus offers two paid versions: Optimus HQ ($29 per year) and Optimus HQ Pro ($149 per year). Both paid versions enable HTTPS connection to the Optimus compression server, conversion for WebP images, and access to the developer API. Optimus HQ Pro is better for those who manage multiple sites since it provides a license for all customer sites.
3. EWWW Image Optimizer
The EWWW Image Optimizer plugin functions similarly to our first two recommendations in that it automatically optimizes images as you upload them to your site, and you also have the option to optimize previously uploaded JPG images individually or in bulk. EWWW’s compression is lossless.
But, EWWW comes with some extra perks that make it stand out. The plugin allows for unlimited file sizes, so you won’t need to worry about large, uncompressed images. Plus, the premium API version can handle PNG, GIF, and WebP files, which is great for sites that incorporate all of these file types. Lastly, EWWW Image Optimizer has a support team that answers all questions, including those from free users.
4. ShortPixel Image Optimizer
The freemium image optimization plugin ShortPixel offers two different image compression solutions, lossless and lossy. Lossy compression means some data is deleted from the file, resulting in much smaller files but slightly lower image quality. If you want to choose between these methods, try ShortPixel.
One of the best parts of this plugin is that it stores the original copy of the image, making it easy to restore if needed. It also comes with other small benefits including CMK to RGB conversion and image rescaling. And, ShortPixel allows compression for JPG, PNG, GIF, WebP, AVIF, and PDF files without size limits.
ShortPixel lets users optimize 100 images per month for free, and charges monthly for additional images. For example, you can pay $3.99 per month for 7,000 images per month, $8.33 per month for 16,000 images per month, and so on.
5. Compress JPEG & PNG Images
Compress JPEG & PNG Images automatically optimizes your JPGs and PNGs by integrating with the image compression services TinyJPG and TinyPNG. These tools analyze the content of the image and choose the best compression strategy without compromising image quality. This compression includes reducing or eliminating metadata, distracting artifacts, and removing redundant data.
Compress JPEG & PNG Images will automatically optimize all images as you upload them in the background, plus images already uploaded to your site. There are also plugin options to keep certain metadata in your images, like copyright and geolocation, as well as a CMYK-to-RGB converter and no file size limits. However, you are limited to around 100 images a month for free. After that, you’ll need a paid account.
6. Imsanity
If you’re looking for an image optimizer plugin that resizes instead of compressing, try Imsanity. This free plugin changes the dimensions of images as you upload them to your WordPress site. It’s unique in that you can specify a maximum width, height, and quality level, and it will detect and resize any images that exceed those parameters, making it ideal for websites that have less-stringent image requirements across the board.
Imsanity also offers a bulk resize feature for any previously uploaded images and can convert less optimized file types (such as BMPs and PNGs) to less bulky JPG formats. Overall, this plugin is best for content-heavy sites, such as blogs, that require authors to upload their own images. Instead of relying on contributors to size images themselves, use Imsanity to automate the process.
Note that Imsanity does not apply compression beyond the WordPress default compression. However, you can use an image compression plugin in conjunction with Imsanity to further compress your resized images.
To learn more about this powerful plugin, check out our in-depth look at Imsanity.
7. Imagify
Like several of the previous options here, Imagify compresses your newly uploaded images as well as images currently in your WordPress media folder. Everything is handled automatically, saving you time and improving your workflow.
One notable feature of Imagify is its three optimization levels, which you can toggle in the plugin settings. The three options are lossless compression, lossy compression, and strong lossy compression for the smallest image files but the lowest image quality. This gives you more control over the degree of quality and file size.
Imagify is compatible with WooCommerce, NextGen Gallery, and other popular plugins, making it ideal for sites with a lot of images that need to be compressed. In addition, Imagify has a backup option where you can restore the original version at any time and begin again.
8. reSmush.it
reSmush.it is the official WordPress plugin for the reSmush.it image compressor, which applies one of several compression algorithms to each image you upload. It allows you to compress images up to 5 MB for free, and you can bulk optimize images in just two clicks.
Importantly, reSmush.it creates a copy of the original image and works off that copy for compression, ensuring that you never lose the original. It also has a sliding scale for optimization level for finer control over compression level.
9. Kraken Image Optimizer
This plugin works with the Kraken.io API, an image optimization service that supports both lossless and lossy compression. Kraken offers image optimization in addition to other features such as a Page Cruncher and Dropbox compatibility. Optimization is performed through Kraken’s infrastructure and adding the output to your WordPress library.
Besides compression, the plugin automatically resizes images upon upload based on designated maximum dimensions, and it has a bulk action menu to handle multiple images in one go.
Also of note is the file size limit, which is a generous 32 MB per file. However, you’re limited to 100 MB of images per month on the free version. There are five paid plans for increased file size limits, ranging from 500 MB per month for $5 per month to 60 GB of images per month for $79 per month,
10. WP Compress
Finally, we have WP Compress, an image optimization plugin that shrinks file sizes using local image optimization and live image optimization. It also offers adaptive images by device, retina device support, and image lazy loading. File compression is completely automated.
WP compress also uses a CDN to serve images as fast as seven milliseconds without needing to make them so small, and it offers a number of features for agencies who may be working with multiple client sites. Together, these features make WP Compress a strong contender for those managing multiple client sites.
Which WordPress image optimizer plugin performs best?
To test out our top plugins, we ran a test JPG image and PNG image through each plugin’s free version on the default compression settings. Here’s what we found:
JPG
For our JPG test, we used the following image with an original file size of 350 KB:
Plugin | Original File Size | Compressed File Size | % Saved | Compression method |
Smush* | 350 KB | 340 KB | 3% | lossless |
Optimus | 350 KB | 150 KB | 57% | lossy |
EWWW Image Optimizer | 350 KB | 325 KB | 7% | lossless |
ShortPixel Image Optimizer | 350 KB | 123 KB | 65% | lossy |
Compress JPEG & PNG Images | 350 KB | 266 KB | 24% | lossy |
Imagify | 350 KB | 154 KB | 56% | lossy |
reSmush.it | 350 KB | 318 KB | 9% | lossy |
Kraken Image Optimizer | 350 KB | 330 KB | 6% | lossy |
WP Compress | 350 KB | 263 KB | 25% | lossy |
* Smush only compresses full images in the Pro version. This result is from the largest image resizing created by the plugin from the image.
PNG
For our PNG test, we used the following image with an original file size of 61 KB:
Plugin | Original File Size | Compressed File Size | % Saved | Compression method |
Smush* | 61 KB | 45 KB | 26 % | lossless |
Optimus | 61 KB | 46 KB | 25% | lossless |
EWWW Image Optimizer | 61 KB | N/A (premium) | N/A (premium) | N/A (premium) |
ShortPixel Image Optimizer | 61 KB | 12 KB | 80% | lossy |
Compress JPEG & PNG Images | 61 KB | 41 KB | 33% | lossy |
Imagify | 61 KB | 25 KB | 59% | lossy |
reSmush.it | 61 KB | 23 KB | 62% | lossy |
Kraken Image Optimizer | 61 KB | 19 KB | 69% | lossy |
WP Compress | 61 KB | 18 KB | 70% | lossy |
* Smush only compresses full images in the Pro version. This result is from the largest image resizing created by the plugin from the image.
Plugins for Smaller Image Files
Images no doubt enhance a website, but they can do more harm than good if they impact load time. By optimizing the images on your site, you’re taking an important step toward better SEO and an improved user experience for your website visitors.