Interaction to Next Paint

SEO

Also: INP

INP = the slowest response time across all your interactions on a page, measured in milliseconds
Good scoreUnder 200ms
Needs work200ms to 500ms
PoorOver 500ms
ReplacedFirst Input Delay (FID)

Quick definition

Interaction to Next Paint (INP) is a Core Web Vitals metric that measures how quickly a page responds when someone clicks, taps or presses a key. Google records every interaction during a visit and reports the slowest one. It replaced First Input Delay (FID) as an official ranking metric in 2024.

How it varies across Australia

Australian sites running heavy third-party scripts, live chat widgets and personalisation tools tend to show weaker INP than sites with leaner tech stacks. Ecommerce checkout pages are a common failure point because they stack tracking pixels right where interaction load is heaviest.

See digital maturity scores across Australian industries

What it actually means

Think of INP as a light switch test. You flip the switch expecting the light to come on straight away. If there's a noticeable pause, something feels broken even if the light eventually turns on. INP measures that pause, but for every button, link and form field on your page.

INP replaced First Input Delay (FID) in Google's Core Web Vitals lineup in March 2024. FID only measured the delay before the browser started responding to the very first interaction. INP is stricter. It watches every interaction across the whole visit and reports the worst one, which makes it a much better proxy for how a site actually feels to use.

The usual culprit behind poor INP is JavaScript. Heavy scripts running on the main thread block the browser from responding to clicks, even when the click itself is simple. Third-party tags, ad scripts, chat widgets and clunky frameworks all compete for the same thread. The fix is rarely one big change. It's usually a dozen small ones: deferring non-critical scripts, breaking up long tasks, and trimming what runs on page load.

INP is the light switch test. Flip it and the room should light up immediately, not after a pause you can feel.

How to calculate it

INP = the slowest response time across all your interactions on a page, measured in milliseconds

Worked example. A visitor clicks 'Add to cart' and the button responds in 90ms. Later they open a dropdown menu that takes 340ms to respond because a tracking script is running at the same time. Their INP for that visit is 340ms, the worst of the two, which falls into the 'needs improvement' band.

The Australian context

Australian ecommerce sites often add multiple tracking and personalisation tools stacked on checkout pages, which is exactly where INP damage compounds. A slow response on a checkout button doesn't just hurt Core Web Vitals, it hurts conversion rate directly, since hesitation at checkout is where abandoned carts start.

Where people get this wrong

Confusing INP with page load speed.INP measures responsiveness to interaction, not how fast content first appears. A page can load quickly and still have terrible INP if scripts block the main thread once someone starts clicking.
Testing INP with a quick manual click and assuming it's fine.INP is measured from real users across an entire session, not a single click during a demo. A site can feel fine to a tester and still fail INP under real traffic with real third-party scripts loaded.
Fixing LCP and ignoring INP because it's the newer metric.INP became an official ranking factor in 2024 and carries real weight. Teams that only optimise for loading speed leave a whole category of user experience problems unaddressed.

Interaction to Next Paint vs Core Web Vitals

Interaction to Next PaintCore Web Vitals
What it isOne specific responsiveness metricThe umbrella of three metrics including this one
MeasuresDelay before the page reacts to a click or tapLoading, responsiveness and visual stability together
Pass thresholdUnder 200msAll three sub-metrics must pass together
When to check itDiagnosing sluggish forms, menus or buttonsGetting an overall picture of site performance

Related terms

Common questions

What replaced First Input Delay as a ranking factor?

Interaction to Next Paint (INP) replaced First Input Delay (FID) in March 2024. FID only measured the delay before the first interaction was processed. INP measures every interaction across a visit and reports the worst one, giving a fuller picture of responsiveness.

What is a good INP score?

Under 200 milliseconds is considered good. Between 200 and 500 milliseconds needs improvement. Over 500 milliseconds is poor and likely affecting both user experience and search rankings. Google measures this from real Chrome users, not lab tests.

Why is my INP bad if my page loads fast?

Loading speed and responsiveness are separate things. A page can render its content quickly and still have heavy JavaScript running afterwards that blocks the browser from reacting to clicks. Third-party scripts and tracking tags are common causes.

How do I fix poor INP?

Reduce and defer JavaScript that runs on the main thread, break long-running scripts into smaller tasks, remove unnecessary third-party tags, and audit anything running during checkout or form submission. Small cumulative fixes usually beat one big rewrite.

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About New Rebellion

New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.

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