---
title: "Check cohort membership"
method: POST
path: "/sdk/v1/cohorts/membership"
tags: ["SDK Cohorts (V1)"]
---

# Check cohort membership

`POST /sdk/v1/cohorts/membership`

## Request

- Base URL: `https://api.gamebeast.gg`
- URL: `https://api.gamebeast.gg/sdk/v1/cohorts/membership`
- Auth: API key in header `authorization`

Resolves whether each provided `userId` is a member of the named cohort for the calling application/environment. Results are served from a per-user Redis cache where possible and computed against ClickHouse otherwise. If the cohort does not exist, returns `cohortExists: false` with `isMember: false` for every user. Rate-limited to 60 requests per minute per SDK key.

## Headers

- `isstudio` union
  - boolean
  - 'true' | 'false'
- `project-id` integer

## Request body

- object
  - `cohortName` string, required
  - `userIds` string[], required

## Response `200`

Default Response

- object
  - `cohortExists` boolean, required
  - `users` object[], required
    - `userId` string, required
    - `isMember` boolean, required

## Changes

- **2026-09-26** `8541dcfed596`: 1 breaking, 3 info
  - the response's body type changed from `array` to `object` for status `200`
  - for the `header` request parameter `project-id`, the exclusiveMinimum was decreased from `true` to `0.00`
  - added the required property `cohortExists` to the response with the `200` status
  - added the required property `users` to the response with the `200` status
- **2026-09-25** `6038ecabdc8b`: 1 info
  - api operation id `checkCohortMembership` was added

[Operation history](https://skmtc.dev/gamebeast/apis/gamebeast-api/changes/sdk/v1/cohorts/membership/post.md)

---

[API](https://skmtc.dev/gamebeast/apis/gamebeast-api.md) - [All operations](https://skmtc.dev/gamebeast/apis/gamebeast-api/llms.txt) - [OpenAPI document](https://skmtc.dev/gamebeast/apis/gamebeast-api/revisions/24605f243ed0?raw)