01 · URL
Enter a URL with important actions
Choose an accessible page with buttons, menus or input fields. Keep test conditions the same when comparing runs. An automatic test does not replay every visitor journey.
Check INP after a click
Does a menu, filter or cart respond slowly? Check INP in a test run and find scripts that delay the page’s response to an action.
What INP is
INP is the pause between an action and the visible page response
The metric is not about how fast the page loaded, but how fast it responded after a click, tap, or input. That makes INP especially important for forms, filters, carts, menus, search, and account areas.
Interaction example
How one click becomes INP
The browser has to receive the event, run the handler, recalculate the interface, and show the next frame. INP measures this whole path.
Event breakdown
example INP386ms
Input delay58msthe event waits for the main threadJS handler178msvalidation, state recalculation, synchronous logicLayout / render83msthe browser recalculates DOM and stylesNext paint67msthe new frame finally reaches the screen
How it works
How Milten checks INP
This INP checker opens the page and tests available interactions automatically. The report separates input delay, JavaScript processing and the next visual update.
02 · SCENARIO
We check interactive scenarios
The scanner interacts with discovered elements and records measured delays. If a target is unavailable or an interaction is not measured, the result does not confirm its performance.
03 · PLAN
Get causes and a fix order
For example, a menu opens slowly. Compare input delay, JavaScript processing and presentation delay. Split heavy work, then repeat the test and compare each part.
FAQ
Frequently asked questions about INP checks
Short answers about Interaction to Next Paint, Core Web Vitals, SEO, and practical interface optimization.
What is INP and why does it matter?
INP is the Core Web Vitals metric for interface responsiveness. It shows how much time passes between a user action and the page's next visual response. A good value is up to 200ms at the 75th percentile.
How can I check my website INP?
Sign in and choose a plan that includes INP. Enter the page URL, choose a device profile, and start the check. Milten tests interactions in the browser and shows delays and recommendations.
How is INP different from TBT?
TBT measures main-thread blocking during loading. INP measures interaction latency. This diagnostic run helps locate a cause; it is not the field INP of real visitors over an observation period. CrUX data may be unavailable for a particular URL.
What should I do with poor INP?
First find the specific interaction with the highest contribution: a button, filter, form, menu, or checkout. Then check long tasks, synchronous handlers, unnecessary render work, forced reflow, and third-party scripts.
How long does INP analysis take?
A quick check usually takes less than a minute, but exact timing depends on the selected region, network profile, CPU throttling, and number of interactive scenarios. For stable conclusions, compare several runs under the same conditions.
Related services
What to check after INP
Back / Forward cache
Check whether the browser uses its cache when navigating back and forward. Find out what prevents caching.
CheckMemory leaks
Find data that stays in memory after repeated navigation. Review possible leaks and accumulating data.
OpenJavaScript check
Check JavaScript files, loading errors, and code unused during loading. Find scripts that need further investigation.
OpenLoad speed
Check page loading with your chosen device and network settings. Get speed measurements, findings, and recommendations.
Run scanner