Interaction to Next Paint (INP)
Interaction to Next Paint measures how quickly your page responds when someone taps a button, opens a menu or types into a field. It captures the lag between the action and the screen visibly updating.
INP replaced the older First Input Delay metric because it looks at responsiveness across the whole visit, not just the first click.
How We Improve INP
Improving responsiveness is mostly about doing less work at the moment a visitor interacts, and spreading unavoidable work so the page can still respond. The result is a page that reacts instantly.
- Reduce the amount of JavaScript the page runs.
- Break long tasks into smaller pieces.
- Defer non-urgent work until after interaction.
- Trim third-party scripts competing for attention.
Where INP Bites Hardest
INP problems show up most on the interactive parts of a site — the moments where a visitor is trying to do something and the page hesitates. These are often the points closest to a conversion, so the cost of poor responsiveness is high.
- Opening menus and navigation on content-heavy pages.
- Filtering or sorting long product and listing pages.
- Typing into forms that validate as you go.
- Adding items to a basket or progressing a checkout.
Why Responsiveness Matters
A page can load quickly yet still feel sluggish if it freezes when tapped. That hesitation makes a site feel broken and pushes people to give up.
Common Causes of Poor INP
- Heavy JavaScript that keeps the browser busy when the user interacts.
- Too many third-party scripts competing for the main thread.
- Large, complex pages that are expensive to update on screen.
How We Fix It
- Break up long tasks so the browser can respond between them.
- Remove or defer scripts that are not needed immediately.
- Simplify how interactive components update the page.
Frequently Asked Questions
What is a good INP score?
Under 200 milliseconds is considered good. Above 500 milliseconds feels noticeably laggy to most visitors.
Does INP affect simple brochure sites?
Less so, because they have little interactivity. It matters most for forms, filters, dashboards and online stores.
If you need a hand with any of this, your Progressive Robot delivery team is ready to help. Raise a ticket from the Support area of your client portal or speak to your account manager and we will guide you through the next steps.