If you have noticed a new metric in Google Search Console, you are likely seeing INP (Interaction to Next Paint). INP is now an official Core Web Vital and has replaced First Input Delay (FID). Unlike FID, which measured only the first interaction, INP looks at how quickly your website responds to user interactions throughout the entire visit.
This guide explains what INP means, how it is different from FID, why Google replaced FID, and how this change can affect your website’s performance and user experience.
Clickmasters SEO Agency UK helps businesses improve INP, LCP, and CLS through technical SEO and website optimisation. We identify performance issues, improve page responsiveness, and deliver a faster, smoother user experience.
What Is INP?
Interaction to Next Paint (INP) is a Google Core Web Vital that measures how responsive a webpage is to user interactions. It looks at interactions such as clicking, tapping, and keyboard input and measures how long it takes for the page to provide a visual response.
For example, imagine a visitor is browsing an online store. They click a product filter, select a category, change a product option, and add an item to their cart. Each of these actions requires the browser to process code and update the page.
If the page responds immediately, the experience feels smooth. If the visitor clicks a button and nothing appears to happen for a noticeable amount of time, the website can feel slow or broken.
INP helps website owners identify these responsiveness problems and understand how well their pages respond to real user interactions.
Why INP Matters for Core Web Vitals and SEO
INP (Interaction to Next Paint) matters because it measures how quickly a website responds to user actions such as clicks, taps, and keyboard inputs. A slow response can make a page feel unresponsive and frustrating, even when the content loads quickly.
As part of Google’s Core Web Vitals, INP helps evaluate the overall responsiveness of a website. Improving INP can create a smoother browsing experience, especially on interactive pages such as eCommerce stores, forms, dashboards, and web applications.
A strong INP score can also support your technical SEO efforts by improving page experience and website usability. For this reason, businesses should monitor INP alongside LCP and CLS to maintain a fast, stable, and responsive website.
How Does INP Work?
When a visitor interacts with a webpage, the browser needs to process that interaction before displaying the resulting visual change.
The process generally involves:
- User Interaction: A visitor clicks, taps, or presses a key.
- Event Processing: The browser identifies the relevant event and runs the required code.
- JavaScript Execution: Scripts may perform calculations, update content, or trigger other actions.
- Rendering: The browser calculates the visual changes required on the page.
- Next Paint: The updated content is displayed to the visitor.
INP considers the time required for this interaction-to-paint process. A page with a lower INP generally feels more responsive.
INP vs. FID: What Is the Difference?
Before INP, Google used First Input Delay (FID) as a Core Web Vital for measuring interaction responsiveness.
FID focused on the delay between a user’s first interaction and when the browser was able to begin processing that interaction. This was useful, but it had an important limitation: it only focused on the first interaction.
A visitor may have a fast first click but experience slow responses later while using a filter, opening a menu, submitting a form, or interacting with a web application.
INP takes a broader approach by considering interactions throughout the page visit.
| FID | INP |
|---|---|
| Focused on the first interaction | Considers interactions throughout the visit |
| Measures initial input delay | Measures interaction responsiveness through the next paint |
| Could miss later interaction problems | Provides a broader view of responsiveness |
| Previously a Core Web Vital | Replaced FID as a Core Web Vital |
This means websites should now pay attention to responsiveness across the entire user journey rather than focusing only on the first interaction.
Why Did Google Replace FID With INP?
Websites have changed significantly over the years. Many modern websites rely on JavaScript to create interactive experiences.
Visitors now interact with:
- Navigation menus
- Product filters
- Search boxes
- Shopping carts
- Forms
- Dropdowns
- Tabs
- Interactive calculators
- Dashboards
- Web applications
FID could not fully represent how responsive these experiences remained after the first interaction.
INP was introduced to provide a broader measurement of interaction responsiveness. It helps website owners understand whether users can interact smoothly with a page from the beginning of their visit through later interactions.
What INP Means for Your Website
For most UK site owners, the practical implications fall into three categories:
Your Core Web Vitals scores may have changed without you doing anything. If you were passing under FID, don’t assume you’re automatically passing under INP — it’s a different, stricter measurement, and it’s worth checking your current status directly rather than assuming continuity.
Interactions you never thought to test now matter. Filters, dropdowns, tabs, form submissions, and anything triggered by a click or keystroke anywhere on the page now contributes to your score — not just whatever happens to be the first thing a visitor clicks.
JavaScript-heavy features are under more scrutiny. Sites relying heavily on client-side rendering, large interactive components, or numerous third-party scripts are more likely to see poor INP scores, since these are the most common causes of slow interaction responses.
The good news is that INP issues are generally fixable through targeted technical work — reducing JavaScript execution time, deferring non-critical scripts, and simplifying event handlers — rather than requiring a full site rebuild.
How Can We Measure INP?
There are several ways to check your site’s INP score, depending on how much traffic you get and how detailed you need the data to be:
- Google Search Console — the Core Web Vitals report shows INP status (Good, Needs Improvement, Poor) grouped by URL, based on real field data from actual visitors over a recent rolling period.
- PageSpeed Insights — enter any URL to see field data where available, plus a lab-simulated estimate as a fallback for lower-traffic pages.
- Chrome DevTools Performance panel — lets you record a specific interaction and inspect exactly which script or task caused the delay, useful once you already know a page is scoring poorly.
- web.dev/measure — a quicker option for spot-checking individual pages without digging into Search Console.
One limitation worth knowing: field data requires a minimum level of real traffic through the Chrome User Experience Report (CrUX). Low-traffic pages often won’t have enough data to show a field score, in which case lab data from PageSpeed Insights or DevTools is the best available alternative.
Reporting on INP and Other Core Web Vitals
INP doesn’t exist in isolation — it’s reported alongside LCP (Largest Contentful Paint) and CLS (Cumulative Layout Shift) as one of the three Core Web Vitals. A few things worth knowing about how reporting works in practice:
- Search Console groups by status, not raw score. Pages are bucketed into Good, Needs Improvement, or Poor and grouped by similar URL patterns — useful for spotting whether an issue affects a whole template rather than one page.
- A page needs to pass all three metrics to get a fully “good” Core Web Vitals assessment — a strong LCP score won’t compensate for a poor INP score.
- Data is rolling, not instant. Because scores are based on a 28-day window of real user data, changes you make today won’t be reflected immediately — expect a lag of a few weeks before Search Console shows the full impact of a fix.
- Agencies like Clickmasters build INP monitoring into regular technical audits rather than treating it as a one-time check, since new content, added scripts, or third-party tag changes can quietly reintroduce interaction delays over time.
What’s a Good INP Score?
Google’s thresholds for INP are:
| Rating | Score |
|---|---|
| Good | Under 200 milliseconds |
| Needs Improvement | 200–500 milliseconds |
| Poor | Over 500 milliseconds |
To pass the overall Core Web Vitals assessment, at least 75% of real-world visits to a page need to fall into the “Good” range for INP specifically, alongside meeting the thresholds for LCP and CLS.
It’s worth noting that “good” doesn’t mean zero delay — some processing time is unavoidable, and 200 milliseconds is generally imperceptible to most users. The goal isn’t instant response on every single interaction; it’s making sure the vast majority of real visits feel smooth rather than sluggish.
What Causes a Poor INP Score?
Several technical issues can contribute to poor INP performance.
Heavy JavaScript
JavaScript is responsible for many interactive features, but excessive or inefficient JavaScript can increase the amount of work the browser needs to perform.
Large scripts may keep the main thread busy and delay interaction processing.
Long Tasks
A long task occurs when the browser spends too much time processing a single task. While this task is running, other work may have to wait.
Breaking large tasks into smaller pieces can allow the browser to respond to user interactions more efficiently.
Complex Event Handlers
When a user clicks or taps an element, JavaScript event handlers may trigger additional processing. If those handlers perform too many operations, the interaction can become slower.
Third-Party Scripts
Analytics platforms, advertising tools, chat widgets, tracking systems, social integrations, and other third-party services can add JavaScript to a website.
While these tools can provide useful functionality, too many scripts can increase the amount of work performed by the browser.
Complex Interactive Components
Interactive product filters, dashboards, calculators, menus, and other components may require significant processing when users interact with them.
Poorly optimised components can therefore contribute to higher INP.
Why Choose Clickmasters for Core Web Vitals Optimisation?
Clickmasters helps businesses improve INP, LCP, and CLS through technical SEO and website optimisation. We identify performance bottlenecks, analyze JavaScript and page interactions, and apply targeted improvements to create a faster and more responsive website.
FAQs
Is INP a ranking factor?
Yes, as part of Google’s page experience signals, though it’s a minor factor compared to content relevance and quality. Its bigger impact is usually indirect — sluggish pages tend to see higher bounce rates, which affects business results either way.
Can a page have good LCP and CLS but poor INP?
Yes, and this is increasingly common. Loading speed and layout stability don’t guarantee good responsiveness once a user starts interacting with the page — they’re measuring different things entirely.
Does INP affect mobile and desktop scores differently?
Yes. Mobile devices generally have less processing power, so the same JavaScript-heavy interaction often produces a worse score on mobile than desktop. It’s worth reviewing both separately in Search Console.
How long after a fix will my INP score improve in reporting?
Since INP field data rolls over a 28-day window, expect a lag of a few weeks between deploying a fix and seeing it reflected in Search Console, even though the improvement is live immediately for users.
