Get max capacity of registrants for meeting/webinar

Feature Requests
1

I’m working on a website where we show our meetings and webinars and want to indicate to the user how many “seats” are left. From the zoom portal we can set a max number of registrants for a meeting/webinar, however, there doesn’t seem a way to get this number back from an API.

1 Like
4

ou’re right, Zoom’s API doesn’t directly provide “seats left” information. Here’s a solution:
Use Zoom’s Get Registrant Report: This API call retrieves a list of registrants for a meeting/webinar.
Compare Registrant Count to Max: In your code, compare the number of registrants retrieved from the Get Registrant Report with the maximum number of attendees you set in the Zoom portal.
Calculate Seats Left: Subtract the number of registrants from the maximum number to determine the remaining “seats.”
This approach gives you the dynamic “seats left” information for your website.

5

I’ve noticed that while Zoom doesn’t provide an API to directly retrieve the maximum registrant count, you can still get close to this feature with a workaround. Here are some ways to calculate available seats:

  1. Track Registration Limits Locally: When you set the max registrant count in the Zoom portal, you could store that number on your end, linking it to the meeting/webinar ID. Then, use the /meetings/{meetingId}/registrants or /webinars/{webinarId}/registrants API to count current registrants and calculate the remaining seats by subtracting this count from the max.

  2. Check for Registration Cutoffs: Another way to infer that a meeting or webinar is fully booked is by monitoring the response from the registrants API. When the max registrant limit is reached, the registration API will typically prevent further sign-ups, which you can then display as “No seats left.”

  3. Leverage Webhooks: If you’re using Zoom’s webhooks, you can also monitor registration changes in real time. Each time a meeting.registration_created or webinar.registration_created event is received, update the registration count in your system to show remaining seats based on your stored max capacity.

While it isn’t perfect, these methods can approximate available seating by combining API and webhook data with a bit of local storage.