A page that appears quickly but then responds slowly feels sluggish. You tap a menu and nothing happens for half a second. You type in a field and the letters appear with a delay. Since March 2024 Google measures exactly that feeling with Interaction to Next Paint, INP for short. It replaced First Input Delay as one of the three Core Web Vitals, alongside loading speed (LCP) and layout shift (CLS).
In this article you read what INP measures, how to see whether your site has a problem, the most common causes and what to do about them. Without jargon where it is not needed.
What INP measures
INP looks at every interaction on a page: a click, a tap or a key press. For each interaction the browser measures how long it takes before something visibly changes. At the end of the visit the slowest interaction is reported, with a small correction for pages with very many clicks. That number is your INP.
Google uses three thresholds:
- Good: 200 milliseconds or less
- Needs improvement: between 200 and 500 milliseconds
- Poor: more than 500 milliseconds
Worth knowing: Google judges this on real visitors, not on a test in your own browser. It is the value that 75 percent of your visitors achieve. If many of your visitors use older or cheaper phones, their experience weighs heavily.
Why it matters
Speed is a ranking factor, but not the most important one. Good content beats a perfect score. The bigger gain is in conversion. A visitor who presses a button and sees nothing happen presses again, or leaves. You notice it straight away in forms, shop filters and drop-down menus.
For businesses that advertise it counts double. You pay for every visitor. Every visitor who leaves because the page does not respond is wasted budget.
How to see whether your site has a problem
You do not need expensive tools. Start here:
- Google Search Console: under Experience and then Core Web Vitals you see per group of pages whether INP is good, needs improvement or poor, for mobile and desktop separately. This is real visitor data.
- PageSpeed Insights: enter an address and look at the field data at the top. If INP is orange or red, there is work to do.
- Chrome DevTools: open the Performance tab, throttle network and CPU to an average phone and click through your own page. Long yellow blocks mean the browser is busy with JavaScript and cannot respond.
Focus on the pages that earn money: your homepage, service pages, contact form and the pages your ads send people to.
The five most common causes
1. Too many third-party scripts
Chat widgets, heatmaps, A/B testing tools, social embeds, cookie banners and several tracking pixels all run at once. Every script needs processing time. A click has to wait until the browser has finished all that work.
2. Heavy page builders and themes
Many WordPress page builders load the same large files on every page, even when a page does not use those parts. That makes the page heavy to build and slow to use.
3. Animations that calculate at the wrong moment
Animations are fine as long as they only change transform and opacity. Animations that recalculate the layout on every scroll movement block the browser.
4. Large forms and filters
A form that re-validates everything on every key press, or a product filter that recalculates hundreds of items on every click, produces high INP values.
5. Too many elements on one page
A page with thousands of HTML elements, for example from a big mega menu or endless sliders, is heavy for the browser to update after every click.
What to do about it
Most of the gain comes from a few clear steps. Start at the top and measure again after each step.
- Clean up scripts. List every script running on your site. Remove what nobody uses anymore. Load the rest via Google Tag Manager, and only after consent or after the first interaction.
- Defer chat widgets. Load a chat only when someone clicks it, or after a few seconds. The visitor notices no difference, your INP does.
- Load only what a page needs. A contact page does not need a slider script. Good themes load only the parts that are on the page.
- Give instant feedback. Let a button show right away that it was pressed, even if sending takes a moment. It feels faster and lowers the measured delay.
- Split heavy work. If a script has to calculate a lot, let it do so in small pieces, so the browser can respond to clicks in between.
- Choose light hosting and caching. Fast servers mainly help load time, but a well set up cache also means less happens on the page.
An example from practice
A common picture on small business sites: a WordPress site with a page builder, a chat widget, a cookie banner, the Meta pixel, a LinkedIn tag, a heatmap tool and Google Analytics, all loading right away. On desktop it feels fine. On an average phone the menu responds only after 600 milliseconds.
By switching on the heatmap only temporarily, loading the chat after a click and starting all tags via Tag Manager after consent, INP often drops below 200 milliseconds. Without changing anything in the design. In the numbers you then see more completed forms.
Where not to overdo it
A perfect 100 in PageSpeed is not a goal in itself. What counts is the experience of real visitors and what they do next. A site that just scores green and converts well beats a site that scores 100 but convinces nobody. Use the numbers to find bottlenecks, not to win a contest.
Frequently asked questions
Is INP more important than loading speed?
All three count. Loading speed decides whether someone stays, INP decides whether the page then works pleasantly. A problem with any of the three can cost visibility and conversion.
How fast will I see improvement in Search Console?
Search Console looks at the past 28 days of real visitor data. After an improvement it takes about a month before it is fully visible.
Do I need to rebuild my whole website?
Usually not. The gain is often in cleaning up scripts and deferring heavy parts. Only when the theme or page builder itself is the brake is a lighter build the logical step.
Want to know how your site is doing?
In a free thirty-minute intro call we look together at your speed, your tracking and the pages your ads send people to. You leave with concrete points you can act on right away.
