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If you own a website, manage SEO, or write code, you probably know that Google takes user experience very seriously. In 2021, they introduced Core Web Vitals—a set of metrics used as a ranking signal to measure how fast, stable, and responsive a page is.
In March 2024, Google made a major upgrade to these metrics. They officially retired First Input Delay (FID) and replaced it with a much more rigorous metric called Interaction to Next Paint (INP).
If you want to maintain your SEO rankings and keep your users happy, understanding and optimizing for INP is no longer optional. Here is a straightforward, easy-to-read breakdown of what INP is, why it matters, and how you can fix it.
1. What is Interaction to Next Paint (INP)?
In simple terms, INP measures how quickly your website responds when a user interacts with it. When a user clicks a button, taps an image, or types on their keyboard, they expect immediate visual feedback. They want to see a menu open, an item added to a cart, or a loading spinner appear. INP clocks the time from the exact moment the user interacts to the exact moment the browser updates the screen (the “next paint”).
A high INP score means your site feels sluggish and laggy. A low INP score means your site feels snappy and responsive.
Note: INP specifically tracks mouse clicks, touchscreen taps, and keyboard presses. It does not track hovering or scrolling (unless you are scrolling using keyboard keys like the Spacebar).
The Three Phases of an Interaction
To fully grasp INP, it helps to understand that an interaction isn’t just one single event. It is broken down into three distinct phases, all of which count toward your total INP time:
- Input Delay: The time between the user clicking/tapping and the browser actually receiving the command (often delayed because the browser is busy doing other things).
- Processing Time: The time it takes for your website’s code (usually JavaScript) to figure out what to do with that click.
- Presentation Delay: The time it takes for the browser to draw the new visual update on the screen.
2. Why Did Google Replace FID with INP?
First Input Delay (FID) was a good starting point, but it had major blind spots. It was too easy to pass, and it didn’t accurately reflect the true frustration a user might experience on a slow website.
Here is why INP is a much better, albeit stricter, measurement:
| Feature | First Input Delay (FID) | Interaction to Next Paint (INP) |
| Scope | Measured only the first interaction on a page. | Measures all interactions during the entire visit. |
| Measurement | Measured only the initial input delay. | Measures input delay + processing time + presentation delay. |
| Focus | Gauged the “first impression” of a website. | Gauges the overall, continuous responsiveness. |
Because INP measures the entire lifespan of a user’s visit and calculates the longest (worst) delay they experienced, it provides a highly accurate picture of your website’s real-world performance.
3. INP Thresholds: What is a “Good” Score?
Google evaluates your site based on real-world user data (from the Chrome User Experience Report, or CrUX). To ensure your site passes the Core Web Vitals assessment, your INP score must meet specific thresholds for the 75th percentile of your users across both mobile and desktop.
- Good: 200 milliseconds or less.
- Needs Improvement: Between 200 and 500 milliseconds.
- Poor: More than 500 milliseconds.
If your site consistently takes more than 200ms to visually respond to a click, Google considers that a bottleneck that could negatively impact your SEO and user experience.
4. Actionable Ways to Optimize Your INP
Optimizing INP almost always comes down to freeing up the browser’s “main thread.” The main thread is like a single-lane highway; if a massive JavaScript truck is blocking the lane, user interactions (the smaller cars) have to sit in traffic and wait.
The most effective ways to clear that traffic
- Audit Third-Party Scripts: Marketing tags, analytics, and social widgets are notorious for hogging the main thread. Remove redundant scripts and delay (defer) non-critical ones so they don’t block user interactions.
- Break Up Long Tasks: If you have heavy JavaScript functions that take longer than 50ms to run, break them up into smaller chunks. This allows the browser to pause the code, process a user’s click, and then resume the code.
- Provide Immediate Visual Feedback: INP measures the time until the next paint. If an interaction requires a heavy calculation or a database fetch, immediately show a lightweight loading spinner or a skeleton screen. This satisfies the INP metric while the heavy lifting happens in the background.
- Reduce DOM Size: A massive, deeply nested HTML structure (DOM) forces the browser to work harder to recalculate the layout every time something changes. Keep your page structure clean and simple.
- Avoid Layout Thrashing: Minimize complex visual animations right after an interaction. Heavy blurring, fading, or sliding effects can delay the presentation phase.
NEED HELP WITH CORE WEB VITALS?
At EBIG, we approach technical SEO and INP optimization the same way we approach strategy overall: carefully, transparently, and with long-term growth in mind.
No shortcuts. No vague promises. Just real-world performance improvements that support real business goals.
If you want technical SEO services that make sense for your brand, not just for passing a Core Web Vitals report 👉 let’s talk.