---
title: retention API methods
description: Show retention data over time.
menu:
docs:
name: retention
parent: methods-admin
identifier: methods-admin-retention
aliases: [
"/methods/admin/retention",
"/api/methods/admin/retention",
]
---
## Calculate retention data {#create}
```http
POST /api/v1/admin/retention HTTP/1.1
```
Generate a retention data report for a given time period and bucket.
**Returns:** Array of [Admin::Cohort]({{< relref "entities/Admin_Cohort" >}})\
**OAuth:** User token + `admin:read`\
**Permissions:** View Dashboard\
**Version history:**\
3.5.0 - added\
4.0.0 - support custom roles and permissions
#### Request
##### Headers
Authorization
: {{}} Provide this header with `Bearer ` to gain authorized access to this API method.
##### Form data parameters
start_at
: {{}} String (ISO 8601 Datetime). The start date for the time period. If a time is provided, it will be ignored.
end_at
: {{}} String (ISO 8601 Datetime). The end date for the time period. If a time is provided, it will be ignored.
frequency
: {{}} String (Enumerable oneOf). Specify whether to use `day` or `month` buckets. If any other value is provided, defaults to `day`.
#### Response
##### 200: OK
Monthly retention data for the month of 2022-09, given that 2 users registered during 2022-09 and were active at least once during that month.
```json
[
{
"period": "2022-09-01T00:00:00+00:00",
"frequency": "month",
"data": [
{
"date": "2022-09-01T00:00:00+00:00",
"rate": 1.0,
"value": "2"
}
]
}
]
```
Daily retention data for the week between 2022-09-08 and 2022-09-14, given that 2 users registered on 2022-09-08 and 1 of those users stopped being active after 2022-09-09.
```json
[
{
"period": "2022-09-08T00:00:00+00:00",
"frequency": "day",
"data": [
{
"date": "2022-09-08T00:00:00+00:00",
"rate": 1,
"value": "2"
},
{
"date": "2022-09-09T00:00:00+00:00",
"rate": 1,
"value": "2"
},
{
"date": "2022-09-10T00:00:00+00:00",
"rate": 0.5,
"value": "1"
},
// ...
{
"date": "2022-09-14T00:00:00+00:00",
"rate": 0.5,
"value": "1"
}
]
},
{
"period": "2022-09-09T00:00:00+00:00",
"frequency": "day",
"data": [
{
"date": "2022-09-09T00:00:00+00:00",
"rate": 0,
"value": "0"
},
// ...
{
"date": "2022-09-14T00:00:00+00:00",
"rate": 0,
"value": "0"
}
]
},
{
"period": "2022-09-10T00:00:00+00:00",
"frequency": "day",
"data": [
{
"date": "2022-09-10T00:00:00+00:00",
"rate": 0,
"value": "0"
},
// ...
{
"date": "2022-09-14T00:00:00+00:00",
"rate": 0,
"value": "0"
}
]
},
// ...
{
"period": "2022-09-14T00:00:00+00:00",
"frequency": "day",
"data": [
{
"date": "2022-09-14T00:00:00+00:00",
"rate": 0,
"value": "0"
}
]
}
]
```
If any of the parameters are missing, cohort calculation will fail and an empty array will be returned.
```json
[]
```
##### 403: Forbidden
Authorized user is missing a permission, or invalid or missing Authorization header
```json
{
"error": "This action is not allowed"
}
```
---
## See also
{{< caption-link url="https://github.com/mastodon/mastodon/blob/main/app/controllers/api/v1/admin/retention_controller.rb" caption="app/controllers/api/v1/admin/retention_controller.rb" >}}