Viewer ID
A viewer ID is a label that identifies the same person across many views, so analytics can tell one viewer watching ten videos from ten viewers watching one. It is usually either an ID the app passes in from its own login system or an anonymous ID the analytics SDK stores in the browser.
Why it matters
Without a viewer ID, analytics see anonymous plays and cannot count unique viewers or follow one customer's experience. With one, support teams can answer complaints with facts, and product teams can see whether quality problems hit the same people repeatedly, which is where churn starts.
How it works
- If the viewer is signed in, the app passes its own user ID to the analytics SDK when the player is set up.
- If no ID is passed, the SDK can create an anonymous ID and store it in the browser.
- Every view from that person carries the same ID.
- Analytics group views by ID to count unique viewers and trace one person's history.
Should I send a user ID to video analytics?
Yes, sending a user ID is worth it if you can do so safely. It lets support look up a specific customer's sessions and lets you count unique viewers accurately. Use an internal ID or a hashed value rather than an email or name, so analytics data does not expose personal information.
How are unique viewers counted?
Unique viewers are counted by grouping views by viewer ID and counting distinct IDs. Signed-in IDs are the most accurate. Anonymous IDs stored in a cookie or local storage count the same person twice if they switch devices or clear their browser, so treat anonymous counts as estimates.
Where it's used
Online learning platforms and subscription services pass their own viewer ID so support teams can look up exactly what a paying customer experienced when they complain.
Where it usually goes wrong, and how FastPix handles it
Teams that rely only on anonymous browser IDs cannot link a support ticket to the viewer's actual sessions, and unique counts drift as cookies are cleared.
FastPix Video Data accepts a viewer ID passed by the app at SDK setup, alongside an anonymous FastPix viewer ID stored in a cookie. When a paying customer complains, support can look up what actually happened in their sessions.
