Load a page to pick the element to test. The preview runs the page's own scripts, so you can open a menu or panel by hand before picking what it reveals.
1 Element to tap
The control users tap, usually the hamburger button.
Nothing picked yet
Page won't load in the preview? Enter a selector
2 What should appear optional
Trigger the element yourself in the preview, then pick what it shows. Without this, any visible reaction counts, which is less precise.
Any reaction counts
3 Conditions
Checking the test browser…
starting…
-
ITTI
- ms
Navigation start → the element first responded
Interactivity gap
- ms
ITTI − LCP: looked ready, ignored taps
LCP
- ms
FCP
- ms
TTFB
- ms
Taps before it worked
-
| Run | ITTI | Gap | LCP | FCP | TTFB | First clickable | Taps | Signal |
|---|---|---|---|---|---|---|---|---|
| Waiting for the test browser… | ||||||||
Each run first visits an unrelated site, then arrives at your page cold (HTTP cache, service workers and cache storage cleared) and taps the element every 25 ms from the moment it can be hit until it responds (30 s limit). A real phone tap is used on mobile devices. "Signal" is what proved the response: the element you picked appearing is the strongest; without one, a menu's aria state or the page changing counts. Numbers are relative to navigation start.