Images play a big part in improving the aesthetic appeal of a website, but they can also significantly slow down download times. Image optimization is essential for attaining high scores on Google’s Core Web Vitals, a collection of metrics used to gauge a website’s user experience. This tutorial will go over how to speed up the loading of your website by optimizing images for Core Web Vitals.
Understanding Core Web Vitals
Let’s quickly go through the Core Web Vitals before getting into picture optimization. They are a group of metrics that focus on the user and gauge how quickly and interactively a web page loads. The three main measurements are:
The Largest Contentful Paint (LCP) metric gauges how quickly the page’s largest element loads.
First Input Delay (FID) tracks how long it takes for a page to start accepting input.
Cumulative Layout Shift (CLS) gauges the page’s visual consistency.
Which Core Web Vitals Can Images Affect?
You might be surprised to hear that graphics can impact all Core Web Vitals. Images excessively large or queued for download too late during rendering will typically have a high LCP score. Images could impact the CLS score if the picture dimensions are not fixed or change while the page loads. Finally, they may impact the INP if picture decoding consumes too much main thread effort. Let’s look more closely:
The largest expressive paint
Largest Contentful Paint (LCP), one of the Core Web Vitals, gauges how long it takes for the biggest element on the page—like an image or video—to become visible to the viewer. The LCP score of a website can be drastically lowered if an image loads slowly or is enqueued too late.
Combined layout change
Cumulative Layout Shift (CLS), another Core Web Vital, gauges how much material on a page moves as it loads. When images are not sized correctly or are added to a website after it has already loaded, the layout can change, and other elements may move.
First input delay and INP
The third Core Web Vital, the INP, which gauges how quickly a page responds visually to user interactions, can also be impacted by images. A page may take longer to respond to user interactions if there are too many huge images that need to be decoded, which could result in a low INP score.
How to Optimize Large Media Files and Images for Better Core Web Vitals
Optimizing large media files and images for better Core Web Vitals performance is essential for improving the user experience on your website. Core Web Vitals are a set of user-centered metrics that Google uses to measure the loading performance, interactivity, and visual stability of web pages. Large media files and images can significantly impact these metrics, so it’s important to optimize them.
Here are steps to help you achieve better Core Web Vitals by optimizing your media files and images:
- Choose the Right File Format:
Use modern image formats like WebP, JPEG 2000, and AVIF for images. These formats provide better compression and quality than older formats like JPEG and PNG.
For videos, consider using the WebM format, which offers good compression and compatibility with modern browsers.
- Resize Images and Videos:
Resize images and videos to the exact dimensions needed for their display on your website. Avoid using larger dimensions than necessary.
Use responsive images and the srcset attribute to serve different sizes to different devices and screen resolutions. This helps reduce unnecessary image data for smaller screens.
- Compress Media Files:
Use image and video compression tools to reduce file sizes without compromising quality. Popular tools include ImageOptim, TinyPNG, and Squoosh.
For videos, consider using video compression software or cloud-based services to reduce file sizes.
- Lazy Loading:
Implement lazy loading for images and videos. Lazy loading means that media files are loaded only when they come into the user’s viewport, reducing the initial page load time.
Use the loading=”lazy” attribute for images and the loading=”lazy” property for videos.
- Optimize Delivery:
Use Content Delivery Networks (CDNs) to serve media files from servers closer to your website visitors. CDNs can improve loading times.
Configure your server to send appropriate image and video formats based on the user’s browser support.
- Image Compression and Format Conversion:
Use image optimization plugins and tools to compress and convert images to modern formats automatically. Consider using responsive images with the element to serve different image formats to different browsers.
- Preload Critical Resources:
Use the preload attribute to tell the browser to load important images or videos early, reducing the perceived load time.
- Implement Video Lazy Loading:
For videos, consider using a video player that supports lazy loading. This allows videos to load only when the user interacts with them.
- Monitor and Test:
Regularly monitor your website’s performance using tools like Google PageSpeed Insights, Lighthouse, or GTmetrix.
Conduct real user testing to ensure that your optimizations are improving the user experience.
Remember that ongoing monitoring and optimization are essential to maintain good performance as your website evolves.
Better Core Web Vitals: Why it’s Crucial
Core Web Vitals are a set of user-centered performance metrics introduced by Google to assess the quality of the user experience on a website. They measure three essential aspects of web page performance: loading, interactivity, and visual stability. Achieving better Core Web Vitals is important for several reasons:
Improved User Experience:
Websites with better Core Web Vitals provide a smoother and more enjoyable experience for users. Pages load faster, respond to interactions more quickly, and maintain visual stability, reducing frustration and bounce rates.
Google considers Core Web Vitals as ranking factors for search results. Websites that provide a better user experience.
Core Web Vitals are particularly crucial for mobile users. Mobile devices often have slower connections and less processing power. Optimizing for these metrics ensures your site is mobile-friendly and accessible to a broader audience.
Lower Bounce Rates:
A slow-loading or poorly performing website often leads to high bounce rates, where users leave the site without interacting further. Better Core Web Vitals can help reduce bounce rates and keep visitors engaged.
Faster-loading and more responsive websites are generally more accessible to people with disabilities who may rely on screen readers or other assistive technologies.
Optimizing your website for better Core Web Vitals can reduce server and bandwidth costs since smaller, more efficient files are transmitted to users.
Positive Brand Perception:
Websites that perform well and provide an excellent user experience build trust and a positive perception of your brand or content.
Ultimately, by prioritizing Core Web Vitals, you can create a more user-friendly, accessible, and competitive website that benefits both your audience and your online presence. It’s an essential part of modern web development and SEO strategy.