---
title: "Restrict Capacity"
slug: "how-to-set-and-restrict-your-events-capacity"
updated: 2025-11-11T18:19:53Z
published: 2025-11-11T18:19:53Z
canonical: "docs.blackthorn.io/how-to-set-and-restrict-your-events-capacity"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.blackthorn.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Restrict Capacity

Capacity can be set on either the Event or Event Item (Ticket).

          Ticket Capacity Rolls up to the Event

          

The Event's **Total Capacity** is the sum of **Quantity Available** on all Event Items (Tickets).

The Blackthorn API, by design, does NOT run capacity validations. Users must add their own logic to implement capacity restrictions.

The API intentionally does not trigger the validation on capacity to allow for flexibility for all customers. When sending registrations through the API, customers can utilize their own custom logic to prevent registrations when the capacity is sold out.

The **Status Formula** field is on the Event Item object. If the **Quantity Remaining** is "0", then the **Status Formula** field will show Sold Out. The custom code can evaluate the formula to block the registration once the **Quantity Remaining** is zero.

For an incoming payload:

- 0 is treated as a sold-out.
- Null or empty Events are treated as infinite, and **Total Capacity** is automatically set to “999999”.

## Restrict Capacity per Event Item (Ticket)

When an Event’s **Remaining Capacity** = “0”, then the Event is sold out. If the **Total Capacity** field is left blank, then the **Total Capacity** is set to infinity. On the Event record, the **Total Capacity** field will be “999999”.

When Event Item's **Quantity Remaining** = “0”, then the Event Item is sold out. If the **Quantity Available** field is left blank, then the **Quantity Available** is set to infinity. On the Event Item record, the **Quantity Available** field will be “999999”.

1. Edit your Event Item (Ticket).
2. Navigate to the **Quantity Available** field and enter the amount.
3. Click **Save**.

This also rolls up to the Event Record as **Total Capacity**. ![restrict capacity per ticket](https://cdn.document360.io/f977eec0-500f-40a3-b663-724a51f78075/Images/Documentation/restrict%20capacity%20per%20ticket.png)