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Practical guides — device, browser, network, display, privacy and developer topics.
The user agent is a compatibility label your browser sends with every request — messy because decades of history are baked into it.…
2 min read
Sites combine three layers: what you declare (UA), what you support (features), and what you measure (viewport).…
No single API says phone or desktop — the verdict combines touch, screen, UA and client hints.…
The version sits in the parsed user-agent row — though privacy reduction may shorten it.…
Device pixel ratio is how many physical pixels back each CSS pixel — the reason text looks razor-sharp on phones.…
Compare the screen row with the viewport row: one is your panel, the other is your window.…
Only Chromium exposes even a rounded memory bucket — and many installs hide that too.…
Websites cannot read your CPU model — but they can show core counts and architecture hints where the browser allows.…
Your OS name comes from the user agent plus platform hints, and any device-info page shows it at the top of the report.…
Browsers expose a deliberately limited subset: enough for sites to adapt, never enough to inventory your hardware.…
Open a trusted checker page and read the live table your browser produces — no app to install and nothing to guess.…