Definition
The First Input Delay (FID) is a performance metric defined by Google and the Web Performance Working Group. FID measures the time from the user's click or tap to the initialization of interactions that really affect page behavior. Thus, it is another metric that developers can use to measure and optimize user experience.
Advantages
The biggest benefit of FID is that it is a very specific metric that measures very concrete user behavior. It is a very meaningful measure of the level of user interaction that a page enables. In addition, FID can help developers understand at the page level where areas for improvement are and how they can make changes to improve the user experience.
Disadvantages
One drawback of FID is that it only measures the initial time of certain interactions, not the time that follows. This means that it can be difficult for developers to learn more about user experience and performance at the page level. FID is also not very good at measuring page-level processing times.
Use cases
FID is mainly used to measure user experience at page level. It is mainly used when the developer wants to make a detailed user experience analysis to understand how users respond to specific page interactions in different browsers and devices.
# Examples
One example of how the FID can help optimize the user experience is image rendering. When a user clicks on an image, the FID measures how long it takes for the image to appear on the screen. If the response time for loading the image is long, the developer can make changes to reduce the loading time.
Another example would be the use of First Input Delay in page load speed optimization. When a user clicks on a page, the First Input Delayhow long it takes for the page to load completely. If the load time is too long, the developer can make changes to improve the load time.
Conclusion
The First Input Delay is a metric that can help developers measure and optimize user experience. It measures the time from user click or tap to initialization of interactions that really affect page behavior. FID can help developers understand user interactions at the page level and make targeted changes to improve the user experience.
« Back to Glossary Index