How Lazy Load for Images Works
The process of lazy loading images involves a few key steps:
Initial HTML Markup
Data Attributes
JavaScript Functionality
Loading Images on Scroll
Initial HTML Markup
In the initial HTML markup, you provide a placeholder for each image you plan to lazy load. A small, lightweight image or a transparent GIF is typically used as a placeholder.
Data Attributes
You must include data attributes in image tags to control when the image is loaded into your browser. These attributes specify the source URL of the image and indicate that the image should be loaded when it is displayed on the user's viewport.
JavaScript Functionality
When an image enters the viewport, it will be detected using JavaScript. The JavaScript function swaps the placeholder with the actual image source when the image is close to being displayed on the user's screen, triggering the image's loading process.
Images are loaded in demand as users scroll down the page. This approach makes it very useful for lengthy websites with multiple images, which reduce the initial load time and minimize data transmitted over the network.
Why would you need to easily lazy load images in WordPress?
There are a few benefits when you implement lazy load in WordPress:
Faster Page Loading
Bandwidth Savings
Improved User Experience
Lower Server Load
SEO Benefits
Faster Page Loading
The lazy loading speeds up the loading of the page because it only loads images that are actually viewed by the user, reducing the initial loading time. That's important, because Google uses page speed as a ranking factor in both user experience and search engine optimization.
Bandwidth Savings
By loading images only as they are needed, lazy loading conserves bandwidth. This is really valuable for users on slower or limited data connections.
Improved User Experience
Faster loading of pages and shorter scrolling delays help to create a more pleasant user experience. Users may interact with your web site without interruption caused by slow loading of images.
Lower Server Load
Because not all images are loaded at the same time, your server experiences lower strain, making it better equipped to handle increased traffic.
SEO Benefits
Google and other search engines favor websites that load quickly and offer a better user experience. Implementing lazy loading can improve your site's search engine rankings, especially if you use images in your content and website’s design.
Best Practices for Lazy Loading images
While lazy loading is a powerful optimization technique, there are some considerations and best practices to keep in mind:
Balancing Speed and User Experience
Implement lazy loading carefully, ensuring that essential images load promptly and that users don't encounter empty placeholders for crucial content.
Testing and Monitoring
Regularly test your website's performance and user experience, as the impact of lazy loading can vary based on user behavior, devices, and network conditions.
Accessibility
Ensure that your implementation is accessible to all users, including those with disabilities who may rely on screen readers.
SEO Impact
Monitor your site's SEO performance after implementing lazy loading to ensure it aligns with your SEO goals.
General Methods to Implementing Lazy Loading
There are multiple ways to implement lazy loading for images on a website:
Manual Implementation
Lazy Loading Libraries
CMS and Plugins
Manual Implementation
You can manually add the necessary data attributes and JavaScript code to enable lazy loading for each image. This approach provides full control but can be time-consuming.
Lazy Loading Libraries
Several JavaScript libraries and plugins simplify the implementation of lazy loading. Popular options include "LazyLoad," "Lozad.js," and "Intersection Observer API."
CMS and Plugins
Content management systems (CMS) like WordPress often have plugins available that enable lazy loading with minimal effort. For WordPress, the "LazyLoad Plugin by WP Rocket" and "A3 Lazy Load" plugins are popular choices.
How to easily lazy load images in WordPress
There are several methods to enable lazy loading in WordPress, ranging from manual coding to using plugins. Below, we'll explore two simple methods: using a popular plugin and applying code snippets.
Easily lazy load images in WordPress Using the LazyLoad Plugin by WP Rocket