New Core Web Vitals metric coming: Interaction with next paint
5 mins read

New Core Web Vitals metric coming: Interaction with next paint

Google announced that it is retiring a core Web Vitals metric and replacing it with a newer one that more accurately reflects user experience.

The new metric is called “Interaction to Next Paint” and has been upgraded from experimental to pending status.

Google announced:

“As of today, INP is no longer experimental and is instead considered a pending Core Web Vital metric. This is a new designation to indicate that INP has demonstrated its readiness to replace FID, but we’re not making the change yet.

To give the ecosystem time to adapt, INP will officially become a stable Core Web Vital metric in March 2024.”

First Input Delay (FID)

The Chrome Blog announced that First Input Delay (FID) will be replaced by a new Interaction to Next Paint (INP) metric in March 2024.

The first input delay measures the time it takes the browser to process a user interaction, which is limited to clicks, key presses, mouse clicks, and pointer presses.

The time it takes for a user to click a button and have the button respond is generally blocked by other scripts.

As such, it was seen as a good representation of a website’s responsiveness and user experience.

However, the FID metric was an incomplete measure of responsiveness.

FID only measured delay, which is the time it takes for an interactive element to respond.

FID has not measured how long it takes for the site to respond to these interactions.

The Chrome team looked at several candidates and after about a year released Interaction to Next Paint (INP) with the official status of one experimental metric on May 2022.

INP measures the overall responsiveness of a page, not just lag.

According to Google:

“Chrome usage data shows that 90% of a user’s time is spent on a page after it has loaded.

Therefore, careful measurement of responsiveness throughout the page lifecycle is important. This is what the INP metric evaluates.”

INP is available since May 2022 via PageSpeed ​​Insights and many third-party speed tests.

PageSpeed ​​Insights has also been updated.

A note on the PageSpeed ​​Insights changelog records:

“Interaction to Next Paint (INP) is no longer an experimental metric, but a pending Core Web Vital. This change is reflected in the UI and API.

Specifically for the API, the response now has the INTERACTION_TO_NEXT_PAINT metric, which contains the same data as EXPERIMENTAL_INTERACTION_TO_NEXT_PAINT.

EXPERIMENTAL_INTERACTION_TO_NEXT_PAINT will be removed from the response in 90 days (August 8, 2023).”

Interaction with the next color

INP’s innovation is that it is a more accurate measure of how long it takes for the entire page to respond.

A bad INP is when you click on something and the expected action, e.g. B. a close-up of an image, is not done immediately.

Google’s page on INP explains it this way:

“Good responsiveness means that a page responds quickly to interactions made with it.

When a page responds to an interaction, the result is visual feedback presented by the browser in the next frame that the browser presents.

Visual feedback will show you, for example, whether an item you put in an online shopping cart is actually added, whether a mobile navigation menu has opened, whether the content of a login form is authenticated by the server, etc.

Of course, some interactions take longer than others, but for particularly complex interactions, it’s important to quickly provide the user with initial visual feedback to alert them that something is happening.”

INP is measured in milliseconds:

  • In the INP score, a value below 200 milliseconds means that the page is okay.
  • Anything between 200 and 500 milliseconds means it’s in the gray area where it’s not bad but needs improvement.
  • INP values ​​above 500 milliseconds indicate poor responsiveness.
Next Color Interaction (INP) Measurement ThresholdsScreenshot from Web.dev

What does this mean for publishers and SEO?

Publishers, developers, and SEOs already working to speed up website performance should see positive results with INP.

Pretty much the usual suspects: scripts take a long time to load and get working, it takes too long to fetch a resource, and it takes a lot of time to parse CSS and HTML to make the site display properly.

Google’s page on optimizing for INP explains the following:

“When a user interacts with a page, the first part of that interaction is input lag.

Input lag can be significant depending on other activity on the site.

This may be due to activity in the main thread (possibly script loading, parsing and compiling), call processing, timer functions, or even other interactions happening in quick succession and overlapping each other.”

Ecommerce stores may want to consider what features are critical for a user to start shopping on a page, what scripts are not required, and what features shoppers won’t miss if they are removed.

INP is currently considered a Pending Core Web Vital metric. It won’t become an official key metric for web vitals until May 2024, so May 2024.

Read Google’s announcement:

Progressive interaction next time

Featured image from Shutterstock/Krakenimages.com