They really are free.
From the docs:
- The special Session Replay checkpoint event $mp_session_record is explicitly excluded from billable monthly events and MTU calculations. [Pricing basics; MTU billing]
- For web, when you enable record_heatmap_data (which powers heatmaps, rage clicks, dead clicks, and page leave), those interaction events are also exempt from your plan data allowance. [JS replay heatmaps; Heatmaps overview]
So:
- Replays themselves + $mp_session_record + events generated by record_heatmap_data (including $mp_page_leave, rage clicks, dead clicks, and click heatmap events) do not count toward your billable event volume.
- If you instead use Autocapture clicks to power heatmaps, those Autocapture click events are billable and do count toward your event volume. [Heatmaps overview; JS replay heatmaps]
The 10k/20k replay limits on Free/Growth plans are therefore genuinely free allowances of replay recordings; only your other tracked events (and any Autocapture events you choose to send) count toward event volume. [Session Replay overview; Pricing blog]
