What a browser information checker can actually tell you
A browser information checker displays values reported by browser APIs. Treat them as diagnostic context, not a verified device identity.
Can a user-agent identify the exact system?
The user-agent string can be reduced or overridden. Browser detection based on it is therefore approximate. Chromium also exposes User-Agent Client Hints as an alternative to parsing that string.
What stays on your device?
Nettools reads browser details locally. Its connection request retrieves your public IP; it does not send the displayed screen size, language, time zone, or full user-agent value as an application payload. As with ordinary HTTP requests, the browser may send its standard HTTP headers.
How can these results help?
When reporting a display or compatibility issue, copy only the details relevant to that issue. Compare the browser-reported platform and version with the browser’s own About screen.
Open the browser panel to inspect your current values. Use the networking wiki to interpret connection information separately.