Cumulative Layout Shift (CLS) is a crucial metric for user experience, measuring the stability of web page elements during loading. In WordPress, optimising CLS is essential for ensuring a seamless and frustration-free browsing experience for your visitors. Let’s explore effective strategies to optimise CLS on your WordPress website.
Prioritise Loading Critical CSS
Critical CSS contains styles necessary for rendering above-the-fold content. Loading it first minimises the likelihood of layout shifts.
- Inline Critical CSS: Embed critical CSS directly into the HTML document to ensure it loads with the initial page render.
- Use Tools and Plugins: Leverage tools like Google’s PageSpeed Insights or plugins like Autoptimize to identify critical CSS and optimise delivery.
Optimise and Preload Web Fonts
Unoptimised web fonts can cause layout shifts as they load. Preloading fonts and optimising them are crucial steps.
- Preload Fonts: Add the
rel="preload"
attribute to the font stylesheet link in your HTML head to prioritise font loading.
- Optimise Font Formats: Convert fonts to more efficient formats (e.g., WOFF2) using tools like Font Squirrel or Transfonter.
Set Dimensions for Images and Media
Images and media without specified dimensions can trigger layout shifts as they load. Always define width and height attributes.
- Explicit Width and Height: Add
width
andheight
attributes to image tags to reserve space before the actual content loads.
- Use Responsive Images: Implement the
srcset
attribute for responsive images to load the appropriate size based on the user’s device.
Read: The Most Important Core Web Vitals Metrics
Lazy Load Images and Media
Implementing lazy loading delays the loading of off-screen images until the user is about to see them, reducing initial page render CLS.
- WordPress Plugins: Use plugins like Lazy Load by WP Rocket or A3 Lazy Load to enable lazy loading for images and media.
- Native HTML Lazy Loading: For modern browsers, consider using the
loading="lazy"
attribute directly in your image tags.
Avoid Dynamically Injected Content
Content injected dynamically after the initial page load can cause unexpected layout shifts. Ensure that dynamically added elements do not affect the page layout.
- Reserve Space: If dynamic content is unavoidable, reserve space for it in the layout to prevent sudden shifts.
- Use Placeholder Elements: Display placeholder elements with dimensions matching the expected content size until the actual content loads.
Optimise Third-Party Scripts
Third-party scripts, if not optimised, can significantly impact CLS. Evaluate and streamline their usage.
- Asynchronous Loading: Load third-party scripts asynchronously to prevent them from blocking other page elements.
- Minify and Concatenate: Minify and concatenate scripts where possible to reduce their overall impact on page load.
Utilise CSS Transitions and Animations Wisely
CSS transitions and animations can cause layout shifts. Optimise their usage and consider utilising transform-based animations.
- Transform Property: Use the
transform
property for animations, as it doesn’t trigger layout recalculations.
- Avoid Sudden Changes: If using transitions, avoid abrupt changes in size or position to minimise layout shifts.
Monitor and Analyse With Web Vitals Tools
Regularly monitor your site’s performance using Web Vitals tools to identify and address CLS issues.
- Google PageSpeed Insights: Use Google’s PageSpeed Insights to assess CLS and receive recommendations for improvement.
- Chrome DevTools: Leverage the Lighthouse performance audit tool within Chrome DevTools for in-depth analysis.
Optimise Theme and Plugin Code
Review and optimise the code of your WordPress theme and plugins to ensure they contribute positively to page loading and layout stability.
- Code Quality: Ensure that your theme and plugins adhere to best practices and are optimised for performance.
- Limit Unnecessary Features: Disable or remove any theme or plugin features that contribute to unnecessary layout shifts.
Regularly Test Across Devices and Browsers
Perform cross-browser and cross-device testing to identify potential CLS variations and ensure a consistent user experience.
- Responsive Design: Confirm that your site maintains layout stability on different devices and screen sizes.
- Browser Compatibility: Test your site across various browsers to catch any CLS discrepancies.
Read: Scaling Your Agency With A White-Label SEO Provider In London
To Sum Up
By implementing these strategies, you can significantly optimise Cumulative Layout Shift on your WordPress website, enhancing user experience and positively impacting your site’s performance metrics. Regularly reassess your site’s CLS performance and adjust strategies as needed to ensure a smooth and visually stable browsing experience for your visitors.