Tracking unique visitors without cookies
2 days ago
- #Privacy
- #Cookieless Tracking
- #Analytics
- Analytics tools track unique visitors through methods like cookies, localStorage, fingerprinting, and salted hashes, each with trade-offs in accuracy and privacy.
- Margin uses a cookieless approach by deriving visitor IDs from IP addresses and user agents, scoped to a single day to ensure privacy and avoid cross-day tracking.
- Unlike cookies and localStorage, Margin's method does not store data on the user's device, eliminating the need for consent banners under ePrivacy rules.
- Margin's server-side hashing occurs within the user's infrastructure, so raw identifiers never leave their stack, enhancing trust and privacy.
- Day-scoped IDs have limitations: no cross-day unique counts, merging of shared IPs, and identifier churn due to changes in user agents or network conditions.
- For signed-in users, Margin can use session-based identifiers, restoring cross-day tracking and retention metrics without additional consent requirements.
- Cookieless analytics like Margin shift from requiring consent banners to relying on legitimate interest under GDPR, though privacy policy disclosures are still necessary.