Free for 100MB of images. Pricing thereafter starts at $ 5.95 / month for 1GB of images.
What is image optimization?
Image optimization is the process of customizing an image to meet certain criteria for your website. These sets of criteria include size, dimension, resolution and correct format. Ultimately, the images should be presented in a way that doesn’t slow down your site or ruin the user experience.
Even in case you are wondering, image optimization and image compression are not the same thing. Image compression is part of the image optimization process where the image size is reduced with the image quality in mind.
How did we test it?
One of the most important aspects of image optimization is image compression – the amount of image file size can be reduced with little or no drop in image quality.
Here we have put together a comparison to evaluate the efficiency of the image compression algorithms used by the listed plugins.
First, let’s see how well the plugin can compress this JPEG image.
Original Image :
Original file size
Optimized file size
Percentage of optimization
ShortPixel adaptive images
0% – says already optimized
Ultra (compression with stronger loss)
Lossy e Lossless
Compression without loss
Next, let’s compare how well they can compress a PNG file.
By now you should have a basic understanding of what image optimization is and how well the different plugins compare to each other when it comes to image compression.
However, image optimization isn’t all about image compression, and you can implement additional methods to optimize images and improve site performance and user experience.
That said, we’ve put together a detailed overview of each of these plugins to give you a better idea of what they have to offer, aside from image compression.
ShortPixel Adaptive Images comes loaded with all the features you need to help you optimize your WordPress images and load your website performance.
You have access to a myriad of features and functionalities, including ShortPixel’s signature compression algorithm. It can help you reduce the image file size by up to 90% without any apparent loss of image quality.
ShortPixel image optimization test
The PNG file experienced a 63.17% drop in file size. Using a lossy algorithm, the final image size went from 1.65MB to 622.27KB.
Check the comparison of the original and compressed image quality.
For the JPG file, we saw a 59.48% reduction from 484KB to 196.11KB.
What’s good about ShortPixel?
Besides its efficient compression algorithm, ShortPixel Adaptive Images has some other great features for optimizing your images and improving website performance.
For starters, the plug-in gives you access to a dedicated Content Delivery Network (CDN) image which is a globally distributed server network. Once a user attempts to access your website, they will deliver images from the geographically closest server which helps with latency in image delivery.
In addition, they also have a smart cropping feature that will dynamically crop and resize images depending on the size and resolution of the visitors’ screen. So if a person is watching from a laptop, it will provide 640 × 480 pixel images. If they are viewing from a cell phone, it will provide images of 300 × 225 pixels.
It also gives you access to slow loading of images . This feature prioritizes the loading of images that are above-the-fold, i.e. immediately visible as soon as the visitor arrives on your web page. The other images are only accessible later when you scroll up, thus reducing the initial load for the server retrieving the website.
Something not so good about ShortPixel?
There isn’t much to complain about ShortPixel with its robust collection of features. However, it’s worth noting that this isn’t a free plugin.
The plugin will allow you to compress around 200 images per month for free. Anything more and you’ll need to upgrade to a premium plan. Additionally, you will need to create a ShortPixel account to continue receiving free 200 image credit.
The plugin follows a freemium model. It basically gives you CDN, Lazy Loading, and image resizing features for free with no limits. However, you’re limited to compressing up to 200 images per month, with a free account.
If you need to optimize even more images, you will need to choose one of their paid plans.
$ 4.99 for 10,000 images / month.
$ 9.99 for 24,000 images / month.
$ 29.99 for 110,000 images / month.
You can also opt for a one-time plan instead of a monthly subscription.
Overall, ShortPixel Adaptive Images is a really powerful and feature-rich option in terms of image enhancement. It comes loaded with tons of great features starting with a powerful image compression algorithm, image CDN, slow loading, and smart cropping.
Plus, the free plan with a limit of 200 images per month is more than enough for hobby bloggers. But if you work with multiple images, the paid plans are also affordable.
Imagify is a popular and powerful WordPress image optimization plugin with over 300,000 active installs.
So what is the reason behind its huge popularity?
Well, this plugin gives you great control and flexibility in terms of optimizing your images. It supports a wide range of file types and also converts your images to the next generation WebP file format.
Imagify image optimization test
Imagify, for some reason, pointed out that the JPG image is already optimized and therefore did not do any compression. For the PNG image, it did a great job compressing the image from 1.65MB to 33.55KB, a 98.02% size reduction. Uses aggressive lossy image compression algorithms for PNG compression.
What’s good about Imagify?
With Imagify, you have access to three levels of image compression from lossless to lossy algorithms. This gives you a lot of flexibility in terms of balancing the right image quality with the image size.
There is also the option to convert an image to WebP format when you optimize it.
Not only that, but the plugin works with all popular image file types, so you shouldn’t run into any kind of compatibility issues.
You can even access an image resizer, which you can use to change the image size right from your WordPress backend.
Anything not so good about Imagify?
However, the biggest problem with Imagify is that it only allows you to optimize up to 25MB of images per month for free. This is extremely low, even for a startup site.
Most of the non-optimized images you will encounter are around 1MB in size. Then, every month, you can use the plugin to optimize up to 25 high-quality or lower images.
You can use the plugin for free to optimize up to 25MB of images per month. For something more, you’ll need to upgrade to one of their premium plans.
Subscription plans start at $ 4.99 / month to optimize 1GB of images and go up to $ 55.99 / month to optimize 50GB of images.
Annual subscription plans and one-time payment plans are also available.
Overall, Imagify offers a lot of amazing features. However, with a monthly image optimization limit of just 25MB for free accounts, it pushes you to opt for a paid plan.
That said, the pro plans are really generous with the image enhancement limit, making Imagify a real bang.
Optimole is a WordPress image optimization plugin that comes loaded with tons of innovative features to help you fully automate all of your image optimization needs.
All you have to do is install and activate the plugin and it will do the rest. You won’t have to worry about any site performance issues resulting from heavy image files.
Optimole Image Optimization Test
Optimole did a good job when it came to compressing JPG and PNG images.
For JPG, it reduced the file size from 484KB to 217.8KB, resulting in a 45% reduction in image size. Uses both lossy and lossless compression.
In the case of PNG, it managed to reduce the image size by 55% using lossy and lossy compression.
What’s good about Optimole?
Optimole comes with a unique feature called dynamic image publishing which basically changes all image URLs to cloud-based URLs.
Now, when a user visits your website, all optimized images will be served by the Optimole server. Your users will have access to high quality images that are dynamically resized and optimized for their specific display.
This approach dramatically improves loading speeds and allows you to truly optimize your images for all devices at the same time. You can even configure it to reduce the image quality in case the user is on a slower connection, just to make sure the website loading speed is not affected.
Anything not so good about Optimole?
The biggest problem with Optimole is that none of the compressed and resized images are stored in the WordPress database. These are generated and served in real time.
As such, you don’t have access to any of the optimized images and there’s no way to reuse them elsewhere.
Optimole comes with a free plan that will optimize your images for around 5000 monthly visits. This is more than enough for a blogger just starting out.
And once your blog / website starts growing, you can easily upgrade to one of their paid plans.
Pricing starts at $ 22.52 / month which will optimize images for up to 25,000 monthly visits and goes all the way up to $ 432.62 for websites that get 3 million monthly visits.
If you’re just starting out with a WordPress website or blog, then going with Optimole makes a lot of sense as you’ll have limited traffic.
You can have tons of images, but as long as your monthly traffic is less than 5000 visitors, you can provide optimized images for free. The plug-in is also perfect for users who want to automate the entire image optimization test and not get stressed out.
However, if you wish to have access to your optimized images, we suggest you use some of the other plugins on the list.
Smush has over 1 million active installs which makes it one of the most popular WordPress image optimization plugins. It is suitable for beginners and known for its ease of use.
The plugin is available in a free version and a pro version, called Smush Pro.
Here we cover the free version of the plugin. However, we will mention the basic differences between the free and premium versions to help you make the right decision.
Smush Image Optimization Test
Smush reduced the image size by 1.6% (484KB to 477KB) using lossless compression.
When it comes to PNG, it achieved 2.4% compression (1.65MB to 1.61MB) using lossless compression.
What’s good about Smush?
Unlike all the other plugins on the list, Smush allows you to optimize potentially unlimited images without having to upgrade to a premium plan.
It uses a lossless image compression algorithm to reduce the image file size without any quality loss.
Plus, you get access to many other image optimization features, including lazy loading, image resizing support, and a dedicated image size detector that can highlight non-optimized images.
By switching to Smush Pro, you can access their Smush Lossy Compression feature which can reduce image size by up to 80%. Other than that, it can automatically resize your images to a pre-configured width and height. You also have the option to convert images to WebP format.
Something wrong with Smush?
The free version of Smush is capable of optimizing images that are less than 5MB. Also, because it uses a lossless compression algorithm, the reduction in image file size is very limited.
Part of the problem is addressed by upgrading to Smush Pro where you get access to lossy compression. Additionally, support for image file sizes has increased to 32MB.
However, neither the free nor the premium version can work with images larger than 32MB.
Smush is completely free.
If you choose to use Smush Pro, it comes with a subscription-based pricing model.
Smush has no limits on the number of images you can optimize, which makes it an attractive offering. However, you are limited to lossless compression with the free plugin, so the image file size will not be reduced by that much.
However, upgrading to Smush Pro gives you more options and you can get more aggressive with the compression algorithm.
EWWW Image Optimizer
EWWW Image Optimizer is another popular WordPress image optimization plugin with over 800,000 active installs.
It connects you with the EWWW IO API which will automatically optimize all images you upload to your website, including images you have already uploaded before installing the plugin.
Similar to Smush, the core plugin is completely free and will allow you to optimize unlimited images. However, there is a premium version of the plugin with many more advanced features.
Here, we will look at the free version of the plugin.
EWWW Image Optimizer: image optimization test
EWWW Image Optimizer managed 3.3% image compression for JPG (484KB to 431.1KB) using lossless algorithms.
For PNG, it compressed the file from 1.65MB to 1.02MB (37.9%) using the pixel perfect lossless algorithm.
What’s good about EWWW Image Optimizer?
For free, EWWW Image Optimizer allows you to optimize potentially unlimited images. Also, the plug-in can work with image files up to 150MB in size, which is huge. Either way, you’re not likely to encounter such a large PNG or JPG file.
In addition to this, EWWW Image Optimizer allows you to apply lossy and lossless compression algorithms that can help you reduce file size by up to 50% without apparent loss of quality.
Something not so good about EWWW Image Optimizer?
The free version of EWWW Image Optimizer lacks most of the important image optimization features besides image compression. There are no image resizing features, options for slow image loading, and so on.
The basic plugin is free with no strings attached.
However, premium plans are available starting at $ 0.002 / image or $ 5-15 / month.
For free, EWWW Image Optimizer offers one of the most robust image compression that is not hampered by annoying limitations. If you’re on a tight budget and need to work with tons of images, the plugin is worth checking out.
However, the lack of other image optimization options means you’ll have to rely on other tools to help with things like image resizing, lazy loading, and so on.
The WP Compress WordPress Image Optimization plugin is an all-in-one solution for all your image optimization needs. And best of all, everything is fully managed and allows you to run everything on autopilot.
You can use it to optimize your site’s images, or you can label it blank and provide image enhancement features to your customers.
WP Compression Image Optimization Test
In our image optimization test, we found that WP Compress optimizes the JPG image from 484KB to 322.35KB (33.4%) using lossless compression.
For PNG, the final image size after compression using lossless is 1.18MB by 1.65MB, resulting in a 28.3% image size reduction.
What’s good about WP Compress?
WP Compress offers a hybrid CDN that combines Google Cloud and BunnyCDN to deliver your images at lightning-fast speeds.
Their image optimization process is based on three distinct characteristics.
First, the images are converted to the next generation WebP format. Then, using the Adaptive Images feature, it optimizes the images for the visitor’s device and screen size. Finally, for the icing on the cake, we have access to the slow image loading feature which further improves website performance.
Something not so good about WP Compress?
There is not much to complain about WP Compress. It’s a well-rounded WordPress plugin for image optimization and ticks all the right checkboxes.
You can use WP Compress for free, but it only optimizes up to 100MB of images per month. This is good enough and good for hobby bloggers or people just starting out.
However, if you need to go over the limit, the price starts at $ 5.95 / month to optimize 1GB of images.
Overall, WP Compress is a solid option for all your image optimization needs. It comes loaded with all the features and functionality you need.
The free plan is also generous enough to allow for up to 100MB of image optimization per month, which is enough for users just starting out.
The benefits of image optimization
With image optimization, you apparently get the same high quality images but with significantly reduced file sizes. This seemingly small thing can help you grow your website in a number of ways.
Here is a list of some of the main benefits of optimizing your website images.
Faster page loading speeds
Images are a necessary part of the modern website, but they also have large files.
If you have too many non-optimized images, it can make your website really heavy, reducing the loading speed. Not only that, but it can also reduce the overall performance of your site and make it slow and sluggish.
Better user experience
Since your website images load faster, it will offer a faster browsing experience to your visitors. This results in a better user experience.
A smaller file size means it will put less stress on your hosting server, in terms of storage space and bandwidth.
Backups will be much faster if your images are optimized and take up less storage space.
What are the types of image files?
As you optimize your images, in some places you will have to choose the best image format. The image format you choose really depends on how you plan to use the image.
Here’s a look at the three most popular image file types, to give you an idea of where and why these formats are used.
The Portable Network Graphics (PNG) image file format normally ends with .png.
The file type is ideal if you’re looking to embed high-quality images for interactive documents and web pages.
The file format follows a lossless compression algorithm. That is to say, the image data is not lost but rather compressed to reduce the file size. As a result, PNGs are relatively higher quality images.
JPEG (Joint Photographic Experts Group) or JPG is one of the most common image file formats.
It typically works with a lossy compression algorithm. Here, the image data is lost or removed, which results in a greatly reduced file size. But at the same time, it can also produce lower quality images.
However, lossless and lossless algorithms can be used on JPEG images. The file format gives you the ability to adjust the image quality to help you achieve the right balance between image quality and file size.
It’s recommended for projects where image quality isn’t too important and you’re willing to sacrifice a few pixels for a lighter image file.
GIF (Graphics Interchange Format) uses only 256 colors and is generally smaller in size. Due to the limited color space, the file size is drastically reduced.
It is the ideal format if you are looking to embed animated images. It’s ideal for web projects because they load quickly and get the message across. You can find GIFs in use on Tumblr pages and even banner ads.
WebP is a relatively newer image format developed by Google and specially curated for website use.
It uses an optimized compression algorithm that takes the best of both worlds: lossless compression and lossy compression. You will be able to get files 20% to 35% smaller than JPEG . But the image quality apparently remains unaffected.
However, as this is a newer file type, only a few select browsers currently support it, including Chrome, Opera, Firefox, and Microsoft Edge.
So that’s a conclusion to our list of the best WordPress image optimization plugins. We hope you’ve found the reading useful and helped you find the perfect image enhancement plugin that meets your budget and needs.
However, if you are still unsure, we recommend using ShortPixel or WP Compress. Both plugins come loaded with all the features and functionality you need to help you optimize your website images.
Plus, their free plans come with a fairly high cap and are enough for blogs and websites that are just starting out.
For others, you can always choose the paid options that suit your needs.