First Input Delay (FID)

First Input Delay (FID) is a Core Web Vital that measures the time from when a user first interacts with a webpage (by clicking a link or tapping on a button) to the time when the browser can begin processing the input.

FID is a crucial metric for evaluating the responsiveness of a website.

Importance in SEO

FID is important for SEO because it directly impacts the user experience. A slow FID can lead to a frustrating user experience, as there is a delay between the user’s action and the website’s response.

Google considers FID as a ranking factor, meaning that websites with better FID scores are more likely to rank higher in search results.

Example

A user clicks on a button to expand a menu, but there is a noticeable delay before the menu expands.

This would be a poor FID experience.

Do

• Optimize the critical rendering path to reduce the time it takes for the browser to render the page.
• Minimize the use of third-party scripts and plugins that can slow down the page’s responsiveness.
• Use browser caching to reduce the amount of data that needs to be loaded on each page visit.

Don’t

• Overload the page with scripts and styles that can delay the browser’s ability to process user input.
• Fail to prioritize user interactions in the development process.
• Ignore FID in performance testing; it should be a key metric in ensuring a responsive website.
• Expect FID to improve without ongoing optimization and monitoring; user interactions can change as the site evolves.