Since its launch back in 2020, Google’s Core Web Vitals (CWV) project has only placed emphasis on three of the six CWV measurements collected by their Chrome User Experience Report data (CrUX). Google announced back in May 2023 that they were replacing one of its metrics, First Input Delay (FID), with Interaction to Next Paint (INP) in March this year, and they have now confirmed it is live.
In this post I’ll be looking at INP, exploring what it is, why it’s a worthy successor to FID and how it aims to improve the user experience of a website.
What is Interaction to Next Paint (INP) and why has it replaced First Input Delay (FID)?
Introduced two years after the launch of CWV and previously relegated to the “Other Notable Metrics” section, Google clearly feels that INP analysis is maturing enough to take centre stage next year. But why has INP replaced FID instead of simply sitting alongside it? Well, the two metrics are quite closely related, with the primary difference being in their scope. FID measures the response of a user’s very first interaction with a page and primarily identifies issues with slow loading and executing JavaScript files. INP similarly tracks the visual response of these user interactions, but unlike FID, its scope is not limited and instead tracks the visual response across the entirety of a page view’s lifecycle. This broader analysis makes it clear that INP is essentially a direct upgrade of FID. More info can be found here relating to FID.
How will Interaction to Next Paint be measured?
Like the other Core Web Vitals, your INP score can be in one of the three thresholds:
- Good: 0-200ms
- Needs Improvement: 200-500ms
- Poor: >500ms
What does my law firm need to know about Interaction to Next Paint?
This development is necessary as a website may have a flawless FID and yet provide an awful user experience after the fact. For example, a website where the cookie consent pop-up has an instantaneous response, but all the other functionality is clunky will still pass FID.
However, under INP, having items such as menus, search filters or shopping baskets with sluggish and delayed visual responses will result in a poor score. These subsequent interactions are arguably more important; a user may forgive some initial slowdown, but consistently poor performance throughout a session will always drive people away.
As such, it’s quite clear why Google has taken the decision to bring it to the forefront of their CWV rating system. Currently, only 65% of websites have a good INP score on mobile.
You want your law firm's website to meet the needs of your clients, so ideally, your website should strive to have an Interaction to Next Paint of 200 milliseconds or less. If your law firm’s website is currently failing its INP score, there are some things you can do to rectify it including:
- Minimising loading delays. This could be done by reducing file and image sizes and removing unused code.
- Shortening processing time. This can be done by reducing the CPU usage of your website.
- Minimising presentation delays. This can be done by simplifying things like HTML and CSS elements, as well as using techniques such as ‘lazy loading’ assets or reducing the size of the Document Object Model (DOM).
Does my law firm still need to worry about First Input Delay?
FID measurements will by no means become obsolete; provided Google continues to track them, the data will still provide useful information about JavaScript load and its initial execution. These first interaction delays may be obfuscated under INP by issues further down the chain of user interactions. It will, therefore, help provide some context towards identifying issues affecting INP. For example, if both INP and FID are poor, taking steps to improve FID may be enough to get your website passing, but if your website’s FID is spot on with poor INP, in theory, you know that the problems are further down the line.
What are the next steps for my law firm and Interaction to Next Paint?
INP has passed the testing and feedback stage and is now an established metric of CWV.
If your website is failing on the INP metric or you have further questions surrounding INP, contact the team at Conscious on 0117 325 0200 or email support@conscious.co.uk, and we can arrange an audit to investigate where the problems may lie and what steps you can take to fix them.