How can I optimize my Webflow site to improve my Lighthouse score? Specifically, I need help with converting images to next-gen format, removing unused JavaScript, eliminating render-blocking resources, efficiently encoding images, reducing the number of fonts loading on page load, improving site speed with a global CDN, defining explicit heights and widths for images, and minimizing main thread work. Thank you!
Optimizing your Webflow site to improve your Lighthouse score involves several steps. Let's go through each of the areas you mentioned:
1. Converting Images to Next-Gen Format:
To convert images to a next-gen format like WebP, you can use tools like Squoosh, which allows you to compress and convert images to different formats. After converting the images, you can replace the original images on your Webflow site with the optimized WebP versions.
2. Removing Unused JavaScript:
To identify and remove unused JavaScript on your Webflow site, you can use a tool like Lighthouse or Google Chrome's Coverage tab. These tools analyze your JavaScript code and show which parts are not being used. Once you identify unused JavaScript, you can remove it to reduce the file size and improve performance.
3. Eliminating Render-Blocking Resources:
To eliminate render-blocking resources, you can load critical resources asynchronously or defer their loading. Webflow offers built-in options to do this. For CSS, you can enable the "Load stylesheets asynchronously" option in the Project Settings. For JavaScript, you can use the "Defer" attribute or move scripts to the end of the body tag.
4. Efficiently Encoding Images:
To efficiently encode images, it's important to strike a balance between quality and file size. Use image compression tools like Squoosh or TinyPNG to reduce the file size without compromising too much on image quality. Ensure that you have set appropriate dimensions for your images in Webflow to avoid rendering larger images than necessary.
5. Reducing the Number of Fonts Loading on Page Load:
Having multiple fonts on your site can impact performance. Consider reducing the number of fonts you use and try to limit them to just a few. Additionally, use font subsets to load only the necessary characters for each font, reducing the overall font file size.
6. Improving Site Speed with a Global CDN:
Using a global Content Delivery Network (CDN) can significantly improve your site's speed by caching static assets like CSS, JavaScript, and images on servers located around the world. Webflow provides its own CDN, so ensuring that your site is published and using the Webflow hosting environment will automatically leverage its CDN.
7. Defining Explicit Heights and Widths for Images:
When you define explicit heights and widths for your images in Webflow, it helps the browser allocate the necessary space while the page loads, preventing content from shifting. This eliminates the need for the browser to recalculate layout, improving the overall performance.
8. Minimizing Main Thread Work:
Minimizing main thread work involves reducing the time spent on JavaScript execution, layout calculations, and rendering. To achieve this, you can optimize your JavaScript code, reduce the number of DOM manipulations, and use CSS animations instead of JavaScript-based animations wherever possible. Additionally, try to keep the overall complexity of your site's layout and styling as low as possible.
Remember to test and measure your Lighthouse score after implementing these optimizations. It's important to note that achieving a perfect score on Lighthouse might not always be attainable, but by following these best practices, you can significantly improve your site's performance and user experience.