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This translation has not been editorially reviewed yet. The German version is authoritative. Deutsche Fassung

Performance

What is INP, and why should responsiveness stay under 200 milliseconds?

INP (Interaction to Next Paint) measures how fast a website visibly responds to input — Google rates up to 200 milliseconds as good, above 500 milliseconds as poor. It's measured across every interaction in a visit: every click, every tap, every keystroke. A page can load fast and still feel sluggish — INP is exactly what makes that sluggishness visible.

Responsiveness is what quality feels like

A visitor taps "Add to cart" — and nothing happens. No colour change, no checkmark, no indication. After half a second, they tap again, and now there are two items in the cart. INP measures exactly these moments: the time between an input and the next visible change on screen. 200 milliseconds is a fifth of a second — beyond this point, people perceive a delay as stuttering. INP looks at the entire visit, so even the one sluggish button that would otherwise disappear behind many fast clicks stands out.

INP comes from real visitor data

INP can only be observed when real people operate the page — a lab simulation doesn't click its way through an entire visit. Google therefore collects the values via real users' Chrome browsers and provides them as field data over a 28-day window. The audit service retrieves this data for your page, provided it has enough views. For low-traffic pages, a related value steps in from the lab: Total Blocking Time (TBT). It measures how long the page is blocked to input while loading, and serves as a lab approximation for INP.

The Google thresholds: 200 and 500 milliseconds

Up to 200 milliseconds, INP counts as good, up to 500 as needs improvement, above that as poor. A common cause of poor values is too much script work in the browser: ad integrations, analytics tools, and elaborate effects keep the device's processor busy enough that input has to wait. On an older mobile phone, this has a much bigger impact than on a new office computer — that's why the audit service measures mobile and desktop separately. In the report, every violation appears with the measured value, the source of the measurement, and the target value alongside it.

  • Operate your website on an older mobile phone: tap the menu, search field, and shopping cart, and watch whether the page responds visibly right away.
  • Ask your agency for a list of all embedded third-party scripts, and together strike out anything nobody needs any more.
  • Make sure every button gives immediate visible feedback — a colour change or a loading indicator — even when the processing behind it takes longer.
  • Check in the report whether your INP comes from field data; if it's missing, your page has too few views for the statistics, and the lab's blocking time takes its place.
  • Repeat the measurement after adding new tools like chat widgets or review modules — additions exactly like these often worsen the value.

Deutsche Fassung dieser Seite

  • Seal Digitale Barrierefreiheit
  • Seal Daten & Recht
  • Seal Technische Qualität
  • Seal Digital Excellence
  • Seal Cyberversicherung

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