Is your WordPress site slow and your pages take forever to load? It's very likely images are the culprit. In this ultimate guide, we'll teach you everything you need to know about how to optimize WordPress images about how to optimize images in WordPress to drastically improve your site's speed and your Google ranking. rankings in Google.
Why optimize images in WordPress?
You may have noticed that, even without any plugins, WordPress automatically reduces the size of any very large very large image you upload. This may lead you to ask yourself: if WordPress already does it, why do I need a plugin or a dedicated process to optimize images? a plugin or a dedicated process to optimize images?
The answer is simple: WordPress default compression is not enough. It is a basic basic measure designed to prevent a 10 MB image of 8000×6000 pixels from crashing your site, but it is far from a true optimization. far from a true optimization. The native system does not focus on reducing the file weight as much as possible without losing noticeable quality. maximum without noticeable quality loss, nor does it convert images to modern and more efficient formats like WebP or AVIF. WebP or AVIF.
Important note: Relying solely on basic WordPress compression is one of the most common mistakes that slow down websites. most common mistakes that slow down websites. You miss out on file size reductions of up to 80% or more, which translates directly into slower load times and slower of up to 80% or more, which translates directly into slower load times and a worse user experience. user experience.
Images are, on average, the most "heavy" file type on a web page. Optimizing your images is the most impactful and effortless action you can take to speed up your site, improve your SEO (Google loves fast sites) and reduce bounce rate. (Google loves fast sites) and reduce bounce rate.
Types of Image Optimization You Should Know About
Optimization is not a single process, but a set of techniques. Understanding them will help you choose the best tool for your needs.
Image Compression (JPEG, PNG)
Compression reduces the file size of an image. There are two types:
- Lossless compression: Reduces the file size without removing any image data. data from the image. The quality is 100% identical, but the size reduction is smaller. Ideal for photographs where every detail counts or for graphics with text.
- Lossy compression (Lossy): Selectively removes parts of the image data that the human eye can barely perceive. that the human eye barely perceives. It offers drastically greater size reduction with minimal or imperceptible loss of quality. loss of quality. For the 99% of cases on the web, this is the best choice.
Conversion to Modern Formats: AVIF and WebP
JPEG and PNG are old formats. Modern browsers support new generation formats that offer much higher compression with the same quality. much higher compression with the same quality.
- WebP: Developed by Google, it offers 25-35% better compression than JPEG with comparable visual quality. comparable visual quality. It is compatible with almost all modern browsers.
- AVIF: It is the latest and most powerful format. It can reduce the size of an image file by 50% compared to JPEG, and 20-30% compared to WebP. by 50% compared to JPEG, and 20-30% compared to WebP. Its adoption is growing growing rapidly.
Good practice: Serving images in AVIF or WebP format is one of the most powerful optimizations you can implement. optimizations you can implement. Most modern plugins can do this conversion automatically. automatically.
Using Appropriate Image Sizes
This is an incredibly common mistake. Uploading a 3000px wide image to display it in an 800px container is a total waste of resources. 800px container is a total waste of resources. The browser has to download the giant image and then shrink it, slowing down the shrink it, slowing down the whole process.
It is crucial that you use images with the correct dimensions for the place where they will be displayed. Tools like Elementor allow you to choose the "Image Size" (Thumbnail, Medium, Large, etc.) when inserting an image element or section background. Always use this option!
Quick guide to image sizes for Elementor:
- Hero background (full screen): 1920px wide is enough.
- Full-width image within the page: Generally between 1200px and 1600px wide width.
- Image in a column (e.g. half page): 600px to 800px wide.
- Images of icons or avatars: 150px to 250px wide.
- Image galleries or customer logos: 300px to 500px wide.
Never use the "Full" option! Unless you have uploaded an image with the exact dimensions and already optimized, selecting "Full" will optimized image, selecting "Full" will load the original file, ignoring the smaller and more efficient sizes that WordPress sizes that WordPress creates.
Lazy Load (Deferred Load)
Delayed loading is a technique that delays the loading of images that are not visible on the screen (i.e. those further down the page). (i.e. those further down the page). The image is only loaded when the user scrolls to it. to it. This drastically speeds up the initial page load time.
The good news is that, as of WordPress 5.5, Lazy Load is a native feature. In addition, constructors like Elementor also implements it by defaultso you generally don't need an additional additional plugin just for this.
Methods to Optimize your WordPress Images
Now that you know the theory, let's look at the practical tools to apply these optimizations.
Option 1: WordPress Native JPEG Quality Setting
You can force WordPress to further compress JPEG images by default. This is done by adding a small
snippet of code to the functions.php of your child theme (never of the parent theme!).
add_filter('jpeg_quality', function($arg){
return 75; // The default value is 82. 75 is a good balance.
});Warning: This method only affects JPEG compression, does not create WebP/AVIF formats, and only applies to only applies to images you upload from now on. Also, modifying theme files can be risky if you are risky if you are inexperienced.
Option 2: Native Combination (WordPress Performance Plugin)
The WordPress development team has an official plugin called Performance Lab. It's a testing ground for new performance features that could make it into the core of WordPress core.
Currently, one of its modules allows the creation and service of WebP images natively. You can install it and activate the "WebP Uploads" module. To apply this to your old images, you will need a plugin such as Regenerate Thumbnails for WordPress to reprocess your entire media library. media.
Option 3: Optimization Plugins (Freemium and Paid)
This is the most common route. Plugins automate the whole process: they compress the images when uploading them, convert them to modern convert them to modern formats and serve them correctly to compatible browsers.
These plugins operate on a credit model or limitations in their free version, offering paid plans to expand their capabilities. plans to extend their capabilities. Below, we analyze them with a homogeneous structure for easy comparison. facilitate their comparison.
Imagify
Backed by the WP Rocket team, Imagify is a guarantee of quality and one of the most popular and reliable options on the market. and reliable options on the market.
- Key Features: It offers three levels of compression (Normal lossless, Aggressive, and Ultra lossy), massive optimization lossy Ultra), massive optimization, conversion to WebP and backup of the original images. original images.
- Free Plan: Allows you to optimize up to 25 MB of images per month (approximately 250 images) and includes WebP conversion. images) and includes WebP conversion.
Smush
Smush is a WordPress veteran with over a million installations. Its long history and constant updates make it a safe and very reliable bet.
- Key Features: Its strength is lossless compression. In addition, it detects images with incorrect dimensions to resize them, detects images with incorrect dimensions to resize them and integrates its own Lazy Load system. Load.
- Free Plan: Allows you to optimize an unlimited number of images, provided that each file weighs less than 5 MB. that each file weighs less than 5 MB. It does not create WebP versions in its free plan.
Elementor Image Optimizer
Released by the Elementor team, this plugin works on any WordPress site but is specially designed for a seamless integration with your builder. specially designed for a seamless integration with your builder.
- Key Features: It is a modern solution that supports WebP and AVIF conversion.
- Free Plan: It offers a test with 200 credits.
ShortPixel Image Optimizer
ShortPixel is considered by many to be the gold standard in image optimization thanks to its powerful algorithms and wide range of configuration options. powerful algorithms and a wide range of configuration options.
- Key Features: Allows granular control over the compression process, offers conversion between formats (e.g. PNG to JPG), and saves a backup copy of the original images for easy restoration. original images for easy restoration.
- Free Plan: To use it, you need to register with an email to get an API key. API. The free plan grants you 100 image credits every month.
Are these plugins worth paying for?
In our opinion, generally do not. While they are excellent tools, the market for free plugins has free plugins has advanced so far that you can get 99% of the benefits without spending a dime.
Option 4: Free Plugins to optimize images in WordPress
This is where the real magic is. You can achieve professional-level optimization with free 100% free tools that, in some cases, outperform the paid ones.
CompressX (The Most Comprehensive Option)
This is our main free recommendation. It is a relatively new plugin but incredibly incredibly powerful and, most importantly, completely free with no credit limits.
- AVIF and WebP support: It allows you to use the most modern and efficient image formats, achieving maximum compression.
- Optimize background images: Its flagship feature is the ability to optimize
images loaded through CSS, such as the
background-imagethat use the Elementor containers via a rewrite. Most plugins (even paid ones) cannot do this. - Free of charge: No limits, no credits, no API required. Install, configure and go.
- For a complete tutorial, visit our dedicated article: How to use CompressX, the best free AVIF and WebP plugin.
Webp Express (The Light & Specialized Option)
If you're looking for a simpler, single-task solution, Webp Express is a fantastic and well-respected option in the WordPress community. respected in the WordPress community.
- WebP Specialist: It does one thing and it does it exceptionally well: it converts your images to WebP format and makes sure they are images to WebP format and makes sure they are served correctly to supported browsers.
- Lightweight and Efficient: By not having so many additional functions, it is a very lightweight plugin that does not overload your WordPress.
- Multiple Delivery Methods: It offers several ways of serving WebP images, ensuring compatibility with almost any ensures compatibility with almost any server configuration.
Jetpack
Jetpack is an all-in-one suite created by Automattic (the parent company of WordPress.com) which includes an image optimization module as part of its performance features.
- Key Features: Its main virtue is its simplicity. It is activated with a single click and works automatically, without complex configurations. It uses its own CDN to serve the images images, which reduces the load on your server.
- Part of the free plan: Image optimization and the use of your CDN are fully available in the plugin's free plan. available in the plugin's free plan.
CDN-Level Optimization with Cloudflare (The Ultimate Solution)
This method is different. Instead of having your server optimize the images, you delegate the task to a Content Delivery Network (CDN) such as Cloudflare. Content Delivery Network (CDN) such as Cloudflare.
The process is as follows:
- You put your site behind Cloudflare (their free plan already offers great speed and security benefits). security).
- Subscribe to your plan Pro (approximately 20$/month).
- In the Cloudflare configuration, you activate the function "Polish".
- Set Polish to "Lossy" and check the box for WebP compatibility.
Advantages of using Cloudflare Polish:
It's a "set it and forget it" solution. You don't need any optimization plugin in your WordPress. Cloudflare intercepts image requests, optimizes them on-the-fly (including conversion to WebP) and serves them from its global network of servers, further reducing latency. It relieves your server from the burden of optimization, which is ideal for shared hosting with limited resources. limited resources.
Conclusion: What is the Best Strategy for You?
We've covered a lot of ground, so let's keep it simple. What should you use?
First, we reiterate: no need to pay for an image optimization plugin. The free or CDN-based alternatives are just as good, if not better.
Scenario 1: You want the best FREE and powerful solution inside WordPress
No doubt about it, install the plugin CompressX. It offers support for AVIF (the most modern format), optimizes Elementor background images and has no hidden costs or limits. It is the best all-in-one all-in-one option that you can manage directly from your WordPress dashboard without spending anything.
Scenario 2: You are looking for the MOST POWERFUL and automated solution, and you don't mind a small investment.
If your site is your business and you want the best possible performance with the least possible effort, the solution is Cloudflare Pro + Polish. Not only does it optimize your images flawlessly and automatically, but you also get all the other benefits of a premium CDN and a top-notch Web Application Firewall (WAF). WAF. It's an investment that goes beyond images and improves the overall speed and security of your site. of your site.
In summary, start by defining the correct dimensions of your images, take advantage of the native Lazy Load and then choose your compression and conversion weapon: CompressX for a free and complete solution complete solution, o Cloudflare Polish for ultimate power and automation. By implementing any of these strategies, you'll see an immediate and measurable improvement in the speed of your WordPress site.
