# Calculate segment size

<YouTube id="tahgIHOUGc0" playlabel="Youtube Video: Learn how to calculate the segment size before sending out your push campaigns"/> 
## How to calculate the segment size

When planning your next targeted campaign, you may want to get an estimate of how many devices receive your push or see your in-app. Pushwoosh makes it easy to calculate the segment size and see the estimated number of subscribers across different communication channels.

After you create a segment, its size is calculated automatically when possible from the conditions you set.

<Aside type="tip">
If the segment view shows "We don't know the segment size yet" and "Click Refresh to get the up-to-date segment size," click the **Refresh** link or **Update segment size** button to run the calculation.
</Aside>

When you change the conditions, the size is recalculated for the new criteria.

<Aside type="note">
The final number of subscribers may change when you launch a campaign due to factors such as subscriber availability or changes in their status.
</Aside>

Once the segment size is calculated, the segment view shows a summary card **Included in segment: devices that match the conditions**.

The card displays:

* **Calculated:** The date of the last calculation, with a refresh icon to run **Update segment size** again.
* **Unique users:** Total number of distinct users in the segment.
* **Devices:** Counts by channel (mobile, web, email, SMS, WhatsApp, Line).

Below the card you see the conditions that define the segment. 

Use **Update segment size** in the header or the refresh icon next to the calculated date to recalculate.

<img src="/segmentation-calculating-segment-size-1.webp" alt="Segment size calculation screen showing subscriber counts for mobile, web, email, SMS, and WhatsApp channels"/>


You can view the segment size in the Segments list, including the number of subscribers for each platform. If the size has not been calculated yet, the list shows "Segment not calculated" and the last modified date.

<img src="/segmentation-calculating-segment-size-2.webp" alt="Segments list view with segment names, estimated sizes, and subscriber counts for each platform"/>

To refresh the segment size from the Segments list, click the three dots next to the segment name and select **Refresh Segment Size** or **Refresh & Export to CSV**.

### Export to CSV

Export this data to a CSV file for further analysis. From the segment detail page, use **Generate CSV for export** in the three-dot menu. [Learn more](/product/audience-data-and-segmentation/segmentation/#export-segment-users)

The CSV file contains information about each user and Tag values. You can use CSV files to send targeted pushes and emails. You can also analyze audience segments to improve your campaigns.