Images are an essential part of a website or blog. Sometimes just an excellent text is not enough. Visual elements are needed to enhance the reader’s impression as our brain process images 60,000 times faster than text.

Of the best worlds, a combination of great content and engaging images is the best solution.

A picture is worth a thousand words” is an old English language adage and is briefly described by the fact that an image can sometimes convey its meaning better and more effectively than a verbal description.

Websites and blogs without images feel pretty dull. Images, graphics, and illustrations are needed. Images also captivate the reader and visitor’s interest and commitment. In the long run, this can lead to more shares, higher rankings, lower bounce rate, increase in sales, more revenue, to name a few benefits.

What Is Image Optimization?

Optimizing images for the web, such as websites and blogs, can be something you may forget when you publish your blog posts or content. However, it is essential and can be done in several ways.

Using WordPress as CMS, there are many excellent WordPress plugins for image optimization, compression, and caching. Both free and premium available. (I list image optimizer WordPress plugins at the end of the post).

Furthermore, several photo editor software is available such as Photoshop, Gimp (Free), and various apps for both Android and iOS, to optimize images for different purposes.

However, in this post, I mostly focus on free image optimizer tools easily accessible online.

With WordPress plugins, the process of optimizing images is usually automated. While with online images optimizer tools, you have to upload your images manually. Maybe it does not gratify everyone.

However, I believe it is an excellent approach because I can decide which quality I want to use, and normally, you have more options than plugins.

In short, image optimization is a process of converting and compressing larger images to the appropriate format, size, and resolution to the smallest possible size without losing sharpness and color.

Why Optimize Images for the Web?

There are a couple of reasons why you should optimize images on your websites and blogs, such as improving website performance and user experience. Furthermore, I have pitched some tips below, which are essential.

Website Load Time – Slow-loading websites is never a pleasant experience for visitors. According to some studies, you have between 3 and 7 seconds to capture your visitors’ attention.

Optimizing your images can help your speed up the loading time of websites. However, slow load time can also be due to other reasons, such as hosting.

Ranking Factors – In fact, Google has used page speed as a ranking factor since 2010. Moreover, in 2018 Google announced that they are also using page speed in mobile search ranking.

So it is essential to try to optimize every aspect of your website, and graphics and images are important elements.

Enhance User Experience – Not only that properly formatted and optimized images provide a faster experience, but optimized images with title and alt improve accessibility and SEO.

You can benefit from Google PageSpeed Insights to test your site and what you can and should do to improve performance and speed. Here is the link to the Google PageSpeed Insights tool.

Image Formats

There are various file formats to choose from, and it can sometimes be a bit confusing to comprehend which image format is best to use for your website.

According to W3Tech’s monitoring, 7.9% of all websites use no images at all. The most used image format is PNG, used by 77.0% of all the websites. Close behind comes JPEG, which is used by 71.8%. Then comes SVG, Gif, and WebP, as you can see in the picture below.

Image Formats
Image source – W3Techs

No matter what file format you use, optimize your images to the correct size, and choose the smallest possible size without losing sharpness and colors.

10 Free Online Image Optimizer Tools

As I mentioned earlier, I mostly focus on free online image optimizer tools in this article. I have tested many tools and conclude that these image optimizer tools on the list are the best image optimizer tools available online. However, if I have missed any tool, please let me know in a comment.

In this article, I have used the same two images, one PNG image, and one JPEG image, on all image optimizer tools to get comparable results.

Original file size – 487.5 KB (PNG)
Original file size – 92.7 KB (JPEG)

After each image optimizer tool, you can read the following metrics original file size, compressed image file size, a percentage reduction, and total saving.

Original File Size – Compressed Image File Size – Percentage Reduction – Total Saving

Let’s take another look at these excellent free image optimizer tools, shall we?

Tiny PNG

TinyPNG is a free image optimization tool to compress both PNG and JPEG image formats.

TinyPNG is a free and easy-to-use image optimization tool to compress both PNG and JPEG image formats. Drag and drop one or more images directly into their box with an easy-to-use drag and drop function – The limit is up to 20 images, max 5 MB each in the free version.

TinyPNG reduces your image files’ file size with a smart lossy compression technology and decreasing colors, which reduces the image size, and smaller bytes are required to store the file. The color reduction is hardly noticeable, and the images retain both sharpness and color.

It is not uncommon to reduce an image file size by more than 70% and get an excellent result. TinyPNG is a prominent online web tool for reducing the size of images without losing sharpness. I have been using this tool for a long time and can recommend TinyPNG to all online users.

Furthermore, TinyPNG – Compress JPEG & PNG images are also available as a WordPress plugin if you want to optimize all your images on your WordPress website automatically.

Original File Size – 487.5 KB (PNG) – 73.8 KB – 85% – Savings 414 KB total.
Original File Size – 92.7 KB (JPEG) – 74.7 KB – 19% – Savings
18 KB total.

Recompressor

Recompressor is a web tool for optimizing and compressing images for better website performance.

Recompressor is another excellent web tool for optimizing and compressing images for better website performance. Their self-explanatory optimizer tool makes it easy to drag and drop images to their website’s selected box.

With both a graph and a table, you can see the file size reduction. Furthermore, it is also possible to choose which image quality you want to download. Moreover, you can choose whether you want to download the image as PNG or JPEG. You also get a full online preview of your optimized image.

With all these options, Recompressor makes one of the most flexible image optimizer tools, and this tool is recommended.

Original File Size – 487.5 KB (PNG) – 267 KB – 44% – Savings – 220.5 KB total.
Original File Size – 92.7 KB (JPEG) – 58.8 KB – 35% – Savings – 33.9 KB total.

Imagecompressor.io

Imagecompressor.io is a free image compression tool for optimizing JPEG and PNG images.

Imagecompressor.io is a free image compression tool for optimizing JPEG and PNG images and preserving and maintaining good image quality.

Imagecompressor comes with several optimization options. You can select an entire folder, and all the images in the folder will be optimized with your selected compression level.

You can also select a single image or several images and choose between compression levels such as Normal, Good, High, and Extreme. Moreover, you can also choose to compress an image to an exact size.

Although Imagecompressor is a free service, they use the latest compression techniques and encoders. MozJPEG to compress JPEG images, and pngquant and ECT to compress PNG images.

It is one of the best online compression and image optimizer tools I have tested. I have used the level – Good compression mode for my selected test images.

Original File Size – 487.5 KB (PNG) – 90.5 KB – 81% – Savings – 385.6 KB total.
Original File Size – 92.7 KB (JPEG) – 55.7 KB – 39% – Savings – 34.8 KB total.

Kraken

Kraken.io is a compression and image optimizer tool.

Kraken.io is a premium (and free) compression and image optimizer tool that comes with five pricing plans. With the pro plans, you also get access to all pro features. However, all free account comes with 100 MB of testing quota.

Furthermore, there is also a free web Interface – Free Online Image Optimizer to optimize and compress images. (It’s the tool I use in this article).

The Kraken Free Online Image Optimizer tool is straightforward to use. Select the source of images. (There is only one option in the free version). Select optimization mode. (Choose between Lossy, Lossless and Expert. Resize your images (optional). (Only available in the Kraken.io PRO).

After selecting your settings, drag and drop the images into the box indicated. The image or images are optimized and are ready to be downloaded directly or via a ZIP file.

Kraken is a perfect free alternative for optimizing images for the web. Smaller file size means that your blog article or webpage loads faster.

There is also a WordPress plugin – Kraken.io Image Optimizer, which unfortunately has not been updated for one year. It has not been tested with the latest three major releases of WordPress.

Original File Size – 487.5 KB (PNG) – 254.15 KB – 46.62 % – Savings 221.94 KB total.
Original File Size – 92.7 KB (JPEG) – 79.60 KB – 12.03 % – Savings 10.88 KB total.

ImageRecycle

ImageSmaller is a free image compressor tool.

ImageRecycle is a PDF and image optimizer tool to optimize your images and PDF files. There is both a free version and pro membership plans for you who may handle batches of images or want more optimization options.

However, I use the free version without registration in this test. With a free trial account, you get access to more features. Furthermore, ImageRecycle is a beneficial image optimizer tool for anyone who wants to optimize images for different purposes.

If I have to designate something negative, ImageRecycle (free version) optimizes and compresses too much, and the images lose both sharpness and color.

There is also a WordPress plugin – ImageRecycle pdf & image compression by ImageRecycle that automatically optimizes and compresses PDF and images. But to use all the features, unfortunately, you have to sign up for a premium plan.

Original File Size – 487.5 KB (PNG) – 82.44 KB – 82.68% – Savings – 393.65 KB total.
Original File Size – 92.7 KB (JPEG) – 58.56 KB – 35.28% – Savings – 31.93 KB total.

Compress PNG/JPG

Compress PNG/JPG is a completely free online image optimizer tool.

Compress PNG / JPG is a completely free online image optimizer tool for compressing images for better website performance and disk space-saving. It is an easy-to-use tool with a couple of accessible settings available.

The approach is self-explanatory. Click on Additional settings – and select compression mode, Low, Medium, or Hight. Medium is the best choice if you want to reduce the file size but still maintain the image quality.

Select images or drag and drop them in the selected box, and the images are compressed quickly and are ready for download.

Compress PNG / JPG is a fast and efficient web tool for optimizing and compressing images. The outcomes are satisfactory and accepted. Give it a try and decrease your website load time and increase the speed of your site.

Original File Size – 487.5 KB (PNG) – 72.2 KB – 85.0% – Savings – 415.3 KB total.
Original File Size – 92.7 KB (JPEG) – 30.7 KB – 66% – Savings – 61,9 KB total.

Compressor.io

Compressor.io is a free image optimizer and online compression tool.

Compressor.io is a free image optimizer and online compression service with fast and efficient optimization. As you probably know, a website’s loading time and speed can improve and boost your SEO ranking. By optimizing and compressing images, you can make your site more speedy, plus it saves space on your server.

Compressor.io supports file formats such as JPEG, PNG, SVG, GIF, and WEBP. Compression types available are lossy, lossless, and custom (only available in the pro version—however, lossy works well for optimizing images for a website.

Upload your images by selecting – Select files or just drag and drop them into the specified box on the website. The images are optimized and compressed quickly and ready to be downloaded. Compressor.io is a fast and neat image optimizer tool. Compressor.io also offers a premium version that offers more features and also supports.

Original File Size – 487.5 KB (PNG) – 254 KB – 46% – Savings – 222 KB total.
Original File Size – 92.7 KB (JPEG) – 85 KB – 6% – Savings – 6 KB total.

ImageSmaller

ImageSmaller is a free image compressor tool.

ImageSmaller is a free image compressor tool that supports PNG, JPG, JPEG, GIF, TIFF image formats. It is an easy to use online tool to optimize images, the load speed, and the ability to improve your site SEO score.

ImageSmaller is a self-explanatory tool. Select your image (max 50 MB), and it will be optimized and compressed within a few seconds.

If I have to mention something negative, it is the limitation of only being able to optimize one image at a time. Similar online services and image optimizer tools usually have multi-image optimization options.

However, ImageSmaller’s large image size of max 50 MB (which many similar image optimizer tools do not provide) can be weighed to their advantage. This is a tool that works easily, quickly, and supports multiple image formats.

Original File Size – 487.5 KB (PNG) – 76.02 KB – 84.03% – Savings – 411.4 KB total.
Original File Size – 92.7 KB (JPEG) – 40.8 KB – 54.87% – Savings – 51.9 KB total.

Optimizilla

Optimizilla is a free online image optimizer tool.

Optimizilla is a free online image optimizer tool usually included in listings as one of the best compression and image optimizer tools.

Optimizilla supports both PNG and JPEG file formats. Their website uses a combination of the best optimization and lossy compression algorithms to optimize and compress images to the minimum possible size and still maintain the required level of quality.

The user interface is self-explanatory. Select images, or drag and drop them in the selected box. You can upload up to 20 images per session. Wait for the optimization and compression to finish.

Click on the thumbnails in the queue for more quality settings. Furthermore, you can use the slider to control the compression level and mouse/gestures to compare images.

Optimizilla is an excellent tool for compressing and optimizing images without losing too much quality.

Original File Size – 487.5 KB (PNG) – 90 KB – 81% – Savings – 397.5 KB total.
Original File Size – 92.7 KB (JPEG) – 73 KB – 20% – Savings – 19.7 KB total.

Squoosh

Squoosh is a free image optimization and compression tool.

Squoosh is an image optimization and compression tool you perhaps not have heard of before? It is a flexible and handy tool for optimizing images with several choices. Initially, there is not much to choose from other than drag and drop an image.

However, once you have selected your image, you will be taken to the next step to decide which image format you want to use. Currently, there is MozJEG, OxiPNG, WebP, AVIF, Browser PNG, Browser JPEG, and Browser WebP file format to choose from.

Moreover, you can resize and reduce the color palette on your selected image. Increase or decrease the quality of your image. Furthermore, there are additional advanced settings; however, they require a bit of knowledge but feel free to give it a try.

Squoosh is a helpful web tool for both beginners and advanced users to optimize images for, for example, your website or blog.

Original File Size – 487.5 KB (PNG) – 261 KB – 46% – Savings – 226.5 KB total.
Original File Size – 92.7 KB (JPEG) – 42.4 KB – 54% – Savings – 50.3 KB total.

* These 10 image optimizer tools you can use to optimize images for the web, websites, and blogs. Of course, there are more similar online image optimizer tools; however, these image optimizer tools presented the best results in my tests.

WordPress Plugins

As I mentioned earlier in the article, there are also several WordPress plugins avaible for you who use WordPress and prefer to install an image optimizer plugin on your WordPress website.

All plugins in the list below are available in the WordPress plugin repository, and you can use one of these plugins to reduce the size of your images for better performance and speed.

  • Smush – Lazy Load Images, Optimize & Compress Image – Smush is a free optimization and compression WordPress plugin created by WPMU DEV. The plugin comes with many features such as lossless compression, bulk smush, automated optimization, Gutenberg block integration, lazy load, and much more. Smush is a good choice for image optimization.
  • EWWW Image Optimizer – EWWW Image Optimizer is an optimizer plugin that can help your website load faster, better performance, and boost your SEO. Furthermore, it is also possible to optimize all your existing images. Features, included: Progressive rendering, intelligent conversion options, secured with SSL encryption, free image backups, and much more.
  • Imagify – Image Optimization & Convert WebP – With the Imagify WordPress plugin, you can optimize images and speed up your website. After installing the plugin, all images are automatically optimized when you upload them to your WordPress installation. Moreover, it is impossible to use Imagify to convert WebP images. Three levels of compression are available – Normal, Aggressive, and Ultra.
  • reSmush.it Image Optimizer – reSmush.it is a free image optimization plugin based on reSmush.it API. The plugin provides image size reduction and accepts JPG, PNG, and GIF files up to 5MB. More features are: Bulk optimize all images, select image optimization level, and it is possible to exclude images.
  • ShortPixel Image Optimizer – ShortPixel is a freemium plugin, which means that there is both a free (limited) version, where you can use 150 images per month for free. The Premium version avaible is Short. Large and XXL, with different price plans. If you have a website and do not upload more than 150 images per month, the free version works fine. Using more images, you need to upgrade for more image use.
  • Optimus – WordPress Image Optimizer – Optimus is also a freemium image optimizer tool and plugin from KeyCDN. After installing Optimus, the image size is automatically reduced. It is possible to save up to 70%, depending on the image and format. Versions available – Optimus (Free with limitation). Optimus HQ (Premium with expanded functionality for personal projects). Optimus HQ PRO (Premium for customer websites).

This was just a small selection of image optimizer and compression WordPress plugins. There are many more plugins in the plugin repository that you can test and compare with the list above. I would love to hear which image optimizer WordPress plugin you use on your WordPress website.

Final Words

The image optimizer tools in the list are not ranked in any way so feel free to test and use any web tool that is presented in my list. However, I can reveal which image optimizer tool I prefer and have used for many years and that is Tiny PNG.

As I mentioned earlier, it is important and necessary to optimize images on websites and blogs. Non-optimized images take up a lot of space and cause web pages to load slowly.

Nowadays, everything must be speedy and fast loading. From a user perspective to search engine ranking factors, optimized images are essential for all website owners and bloggers to be aware of and optimize images in the best possible way.

In the article, we have gone through what image optimization is, why you should optimize images for the web, which image formats are best to use, great online image optimizer tools, and some WordPress image optimizer plugins from the WordPress community.

Whether you prefer to use online image optimizer tools or WordPress plugins, I hope that one or more of the web tools or plugins can help you optimize images on your website or blog in the best possible way.

I would love to hear your opinion about image optimization, online tools, WordPress plugins, or other tools that can be used to optimize images in a comment below.

About the Author

Peter Nilsson

Founder of WP Webify

Peter Nilsson is the founder of websites like WP Webify, WP Newsify, WP Pluginsify, WP Daily Themes, etc. He is a big fan of WordPress and loves to write about WordPress. You find him here at WP Webify all the time! Cheers!

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