Understanding First Contentful Paint (FCP)

First Contentful Paint (FCP) measures the time it takes for the browser to render the first piece of content that appears on a webpage. This can be text, images (including background images), SVG elements, or other content. It reflects how quickly users see something happening on the page, providing a crucial signal of perceived load speed.

Don't confuse FCP with LCP (Largest Contentful Paint), which measures how fast the main content (largest element) becomes visible to the user.

Why FCP Matters?

FCP is a significant performance metric as it impacts the user's first impression of the loading speed. A fast FCP improves the perception of the website's performance, answering the question, "Is this website loading?" If the user sees content appear quickly, they are more likely to stay engaged.

What is a Good FCP Score?

To provide a positive user experience, aim for an FCP of 1.8 seconds or less. The best practice is to measure this at the 75th percentile of page loads, considering both mobile and desktop environments. This benchmark ensures that most of your users experience a fast initial load.

Factor Influencing FCP

- Server Response Time (TTFB)

A lower Time to First Byte (TTFB) helps improve FCP by allowing the browser to start rendering content sooner. This is one of the key factors for a fast FCP.

How to Improve FCP

Here are actionable steps to optimize FCP and make your website feel faster for users:

1. Eliminate Render-Blocking Resources Move critical JavaScript and CSS inlined within the HTML or mark scripts with async/defer attributes to prevent them from blocking the rendering process.
2. Minify CSS Reducing the size of CSS files by eliminating unnecessary characters and formatting speeds up their download.
3. Remove Unused CSS Identify CSS that is not needed for the initial rendering and remove it to reduce the load time.
4. Remove Unused JavaScript Clean up JavaScript that does not contribute to the initial page rendering to enhance load speed.
5. Preconnect to Required Origins Establish early connections to third-party origins, such as fonts or analytics, to speed up resource loading.
6. Reduce Server Response Times (TTFB) Optimize backend processes and use caching strategies to ensure that servers respond quickly to requests.
7. Avoid Multiple Page Redirects Minimize redirects, which cause additional network requests and delays in loading.
8. Preload Key Requests Use the preload attribute for important resources, like fonts or critical scripts, to prioritize their loading.
9. Avoid Enormous Network Payloads Compress assets such as images, scripts, and stylesheets, and serve optimized versions to minimize the amount of data transferred.
10. Serve Static Assets with an Efficient Cache Policy Implement caching strategies for static resources, so users don't need to download the same resources every time they visit the site.
11. Avoid an Excessive DOM Size Simplify the HTML structure to make parsing and rendering faster.
12. Minimize Critical Request Depth Reduce the number of critical resources needed to render the above-the-fold content to enhance initial load performance.
13. Ensure Text Remains Visible During Webfont Load Use font-display: swap to display fallback fonts while custom fonts are still loading, and preload fonts for quicker rendering.