Why is my calculated segment size much smaller than the estimated size shown in the preview?

This discrepancy typically occurs because the segment calculation for push notifications, by default, only includes devices that are currently subscribed and have a valid push token. The segment preview, on the other hand, may estimate the total number of users or devices that match your filter criteria, regardless of their subscription status.

For example, you may have many users who match your tag criteria but have not opted-in to receive push notifications. These users do not have a push token and will be excluded from the final segment count when it is calculated for a campaign, making it appear smaller than the estimate.

To include all devices that match your criteria in the segment count, even those that are unsubscribed:

1. Navigate to the settings of the specific segment you are editing.
2. Find and check the box labeled "Include all user's devices".

Please Note: While enabling this option will make the segment's total count reflect all devices matching your filters, it does not make unsubscribed devices reachable. Devices without a valid push token will still be unable to receive push notifications.