Here's a handy webhook where you can calculate the number of days between dates. You just need to add a new Webhook and install it into the node where you want the calculation to take place. Here's how to set it up:

Step 1: Add the Webhook to your Organization

1. Go to Apps & Integrations.
2. Click on Add Webhook.
3. Give the Webhook a name (like "Number of days"), and enter this for the webhook URL:

https://zingtree.com/apps/webhook/filters/date_difference.php?

The end result looks like this: 

Step 2: Call the webhook from your tree

Somewhere in your tree, you likely have 2 data entry fields that are collecting the first and second dates. Make a note of those date variable names. For example:

Open your tree, and edit the node where you want the date difference to be calculated.

1. Under the Apps / Webhooks section, click Add App.
2. Pick the Webhook you added previously ("Date Difference", for example).
3. In the Message Data area, enter something like this:

   &date1=#date1#&date2=#date2#&var=diff

   Replace #date1# and #date2# with your own variable names for the first and second dates
   
   
4. Save the changes to the node.
   
   

Your edits should look something like this:

Now just use #‌diff# anywhere you want to show the date difference. Example: