First Contentful Paint (FCP)
First Contentful Paint (FCP) is a performance metric used to measure the time it takes for a web page to display its first piece of content on the user's screen. It indicates how quickly the browser can render the first content element (e.g., text, image, or canvas) after the user navigates to the page.
A faster FCP generally results in a better user experience, as it helps users perceive the page as loading quickly. To provide a good user experience, Google suggests sites should strive to have a FCP of 1.8 seconds or less.
Improving First Contentful Paint can be achieved through various optimization techniques including:
- Minimize server response time: Reducing the time it takes for a server to deliver the HTML document is crucial for improving FCP. This can be achieved by optimizing server configurations, using a Content Delivery Network (CDN), and implementing caching strategies.
- Optimize critical rendering path: The critical rendering path is the sequence of steps a browser takes to process and render the first content on a page. To optimize it, minimize the number of render-blocking resources such as CSS and JavaScript files. You can do this by inlining critical CSS, deferring non-critical JavaScript, and using async and defer attributes.
- Reduce file sizes: Compressing and minifying resources like HTML, CSS, and JavaScript files can help reduce the amount of data that needs to be transferred and parsed by the browser. This results in faster content rendering.
- Optimize images: Images can significantly affect FCP. Use image compression techniques, serve images in next-gen formats (like WebP and AVIF), and use responsive images to provide the right-sized image based on the user's device.
- Use font-display: Swap or optional values: Custom web fonts can delay FCP, as the browser must download and parse the font files before displaying the text. Use the CSS font-display property with 'swap' or 'optional' values to allow the browser to display text with a fallback font while the custom font loads.
- Implement HTTP/2 or HTTP/3: Upgrading to the latest HTTP protocols can improve FCP by allowing for multiplexing, server push, and other performance-enhancing features.
- Use resource hints: Implement resource hints like 'preload', 'prefetch', and 'dns-prefetch' to prioritize and fetch critical resources more efficiently.
- Leverage browser caching: Cache static resources, such as images, stylesheets, and scripts, to decrease load times for repeat visits.
These are just a couple of suggestions for optimizing your FCP results. Get into the performance-first mindset with our comprehensive frontend performance checklist.
Remember to monitor and analyze your website's frontend performance regularly, as ongoing optimization is key to maintaining a high-performing site.