At a glance
Sessions Captured is the volume baseline for everything FullStory shows. It is the count of sessions recorded as replays in the period. On its own it tracks site traffic; more usefully, it is the denominator behind every rate card and the canary for capture problems. A sudden drop with no matching traffic drop almost always means the FullStory snippet stopped firing, not that visitors stopped coming. That is why a steep fall here triggers the capture-broken alert.
| What it counts | The number of sessions FullStory captured as replays in the period, across today, 7-day, and 30-day windows. |
| Sample type | Backend API data from FullStory, refreshed on the standard data refresh. |
| Why it matters | It is the denominator for every frustration and conversion rate. A drop that does not match a traffic drop is a tracking failure, not a demand signal, and it invalidates the other cards until fixed. |
| Reading the value | Compare each window to the prior period. A fall greater than a quarter against the 7-day baseline is the trigger for investigating capture. |
| Currency | count |
| Time window | T/7D/30D vsP |
| Alert trigger | drop >25% vsP |
| Sentiment key | fs_session_count |
| Roles | owner, marketing |
Calculation
Calculated automatically from your FullStory data. Vortex IQ counts captured session replays for today, the trailing 7 days, and the trailing 30 days, each compared against the prior equivalent period. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading.Worked example
A representative reading of Sessions Captured for a typical merchant on FullStory. Say the 7-day count usually sits near 18,000 and falls to 11,500, a 36% drop, while ad spend and analytics traffic are flat. That mismatch is the tell: traffic is steady but capture collapsed, so the FullStory snippet is failing on part of the site. The capture-broken alert fires, the team finds a deploy that dropped the script from product pages, and restores it. Without this card the missing data would have looked like a demand slump. For deeper investigation, use Vortex Mind to correlate against traffic; for natural-language exploration, ask Ask Viq whether capture or traffic fell.Sibling cards merchants should reference together
| Card | Why merchants reach for it |
|---|---|
fs_replay_capture_coverage | The coverage ratio that contextualises this raw count. |
fs_alert_tracking_broken | The alert that fires when this count collapses. |
fs_health_score | The composite that capture health feeds. |
ful_sessions | The companion analytics session count. |
Reconciling against the vendor’s own dashboard
Where to look in FullStory’s own dashboard: FullStory shows captured session volume in session search and its overview reporting. Confirm period boundaries and any sampling settings match the Vortex IQ profile to reconcile cleanly. Why the Vortex IQ value may legitimately differ:| Reason | Direction | What to do |
|---|---|---|
| Sampling. If FullStory samples capture, the count reflects sampled sessions, not all traffic. | Lower | Confirm the sampling rate. |
| Period boundary. Vortex IQ uses rolling windows; FullStory dashboards may use calendar periods. | Variable | Match the period range. |
| Bot filtering. Bot and internal-traffic exclusion rules may differ between the two views. | Variable | Align the filters. |