Server request
Values observed at the Cloudflare edge when this page calls the telemetry endpoint /api/whoami.
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Waiting for /api/whoami...
These are server-side values. They can be logged before a user clicks anything.
Browser runtime
Local JavaScript-readable browser, locale, and runtime identity fields.
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Reading local browser attributes...
This page displays them locally. A site could also choose to transmit them.
Hardware & display hints
Approximate device capabilities exposed by browser APIs and media queries.
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Reading screen and hardware hints...
Proxy, TLS & privacy headers
Cloudflare edge, TLS and network context, privacy preferences, and cookie presence.
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Waiting for Cloudflare edge data...
Client Hints headers
Optional browser-supplied hardware/software hints requested by the origin.
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Negotiating Client Hints...
Some hints only appear after the first response advertises
Accept-CH, and many browsers intentionally omit them.Graphics, audio & fonts
Rendering surfaces often used in fingerprinting tests.
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Testing local rendering surfaces...
Hashes are computed locally from tiny off-screen renders. They illustrate stability, not uniqueness.
Privacy & storage state
Browser preferences, permissions states, and local storage availability.
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Reading privacy-related browser state...
Capability surface
Modern APIs that reveal what the browser and device can do.
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Checking exposed API surface...
Local fingerprint demo
A digest of selected local attributes. The digest inputs are shown below and are not posted back.
Demo hash
Computing...
Input count
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Collecting local inputs...
What this demonstrates
The surprise is usually not one field. It is the combination.
Request headers identify context.
User-Agent, Accept-Language, Client Hints, Fetch Metadata, referrer, and proxy headers can describe your browser, language, navigation path, and network route.
JavaScript adds local detail.
Screen geometry, timezone, hardware hints, storage estimates, connection type, permissions states, and rendering quirks can be read without a login.
Privacy tools reduce precision.
Modern browsers may freeze, round, omit, or randomize values. That helps, but correlated low-entropy signals can still be useful to trackers.