1device

Stable, signed, hard-to-spoof identification — client + edge fingerprinting on Cloudflare
Visitor ID
collecting signals…

Confidence

stable signals contributing

Identification

Client signals

Edge / network

Fingerprint hash

stable
SHA-256 over normalized client + edge signals. The visitor id is an HMAC-SHA256 of this hash keyed by a server secret, so it cannot be forged client-side.