The Customer.io Track API allows developers to send behavioral data and customer profile information into Customer.io. It provides endpoints for identifying customers, tracking events, managing devices for push notifications, and sending anonymous events. The API uses basic authentication with a Site ID and API key, and accepts JSON request bodies.
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openapi: 3.2.0
info:
version: 1.0.0
title: Pipelines Track API
description: '# Overview
In general, you''ll consume this API through one of our source libraries—our JavaScript client library or any of our server packages. But you can also integrate directly with our REST API if you don''t want to install one of our libraries or you want to support a source that we don''t have a native integration with.
# Server addresses: US and EU
Customer.io hosts services in the United States (US) and European Union. Select the appropriate server address for your region.
| Region | Server Address |
| :-- | :-- |
| US | https://cdp.customer.io |
| EU | https://cdp-eu.customer.io |
If you''re in our EU region, you''ll need to specify the EU URL when you initialize our server-side libraries. If you use our JavaScript client library, we''ll set your region and route data/calls automatically.
# Get an API key
1. Go to the <svg class="icon"><use href="#connection" /></svg> tab and click **Sources**.
1. Click **Add Source**, pick **HTTP**, and click **Next**.
1. Give the source a *Name* and copy your *API Key*. You''ll use this key to authenticate with our API. If you don''t copy the key now, you can always get it later from the *Settings* tab when you''re done setting up your source.
1. (Optional) Test your connection by sending a test call. You can copy your API key into an app like Postman or send a CURL request. If your request is successful, and then you click *Test Connection* we''ll let you know if your request was successful and you''ve set up your HTTP implementation successfully.
1. Click **Submit**.
Now you can use the key as a username with a blank password to authenticate and send requests to our API.
# Authentication & rate limits
Our API uses basic authorization with an API Key provided when you set up a source. If you use Postman or another platform that helps you send API calls, this API key is the *Username*, and the *Password* is blank.
Our sources are all authenticated using a **API Key** that we generate when you create a source.
## Rate and payload limits
A request is limited to 32KB. A batch request is limited to 500KB total and 32KB per call in the request. If a request exceeds these limits, you will receive a 200 response, but the request will not go through.
The Data Pipelines API has a rate limit of 3000 requests per 3 seconds for both active data integrations and historical backfill scripts. This limit applies to both our v1 and v2 APIs.
While this rate is not strictly enforced, consistently exceeding it may lead to throttling or dropped data, especially during periods of high system load. If we detect a sustained high volume that could impact other customers, we may contact you to help adjust your integration or, in rare cases, temporarily block requests.
<div class="fly-panel fly-light regionUS">
<div class="fly-panel-body us-server">
<p class="text--bold">Warning</p>
<p>Rate limits are subject to change. We may adjust these thresholds to ensure stable performance for all customers.</p>
</div></div>
# Try out our postman collection
We''ve generated a Postman collection with all of the endpoints organized as you''ll find them on this page, with a starter environment (mainly to contain your API key). For our API endpoints, **your API key is your username and your password is blank**.
You''ll notice that payloads on this page can contain significantly more information than the payloads that appear in our collection. We''ve limited our collections to the fields that you''ll _typically_ use when you send calls to our APIs and libraries, so it''s easier to get started. But you can add additional fields to payloads—like `context`, `integrations`, and so on—if you want.
If you fork this collection, you might want to disable the *Watch original collection* option. We automatically update our Postman collection whenever we release changes to our documentation, even if we don''t change our APIs—which happens daily! Rather than being flooded with Postman notifications, you can check out our [Release Notes](/release-notes/) for updates to our APIs.
[<img src="https://run.pstmn.io/button.svg" alt="Run In Postman" style="width: 128px; height: 32px;">](https://god.gw.postman.com/run-collection/23697545-287dd370-3d8b-4a71-80fe-75d6b7c7ff61?action=collection%2Ffork&source=rip_markdown&collection-url=entityId%3D23697545-287dd370-3d8b-4a71-80fe-75d6b7c7ff61%26entityType%3Dcollection%26workspaceId%3D35e4a70d-66bd-4b3e-8a0c-57f9e32080dc#?env%5BCustomer.io%20Data%20Pipelines%20API%20Environment%5D=W3sia2V5IjoiY2RwX2FwaV91cmwiLCJ0eXBlIjoiZGVmYXVsdCIsInZhbHVlIjoiY2RwLmN1c3RvbWVyLmlvIiwiZW5hYmxlZCI6dHJ1ZX0seyJrZXkiOiJ3cml0ZV9rZXkiLCJ0eXBlIjoic2VjcmV0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfV0=)
# Deletions, suppressions, and other semantic events
You''ll notice that this API only contains `POST` calls; we don''t have `DELETE` operations. For delete operations, and other operations that don''t have bespoke endpoints, we use *semantic events*.
When you need to do things like deleting people, removing relationships, and other sorts of things, you''ll send a request to the `/track` endpoint with a specific event `name` parameter. The `name` tells us what to do with the request.
For example, you can send a `track` event with the name `Delete Person` to remove a person from your workspace.
See [Semantic Events](/integrations/data-in/semantic-events/cio-journeys/) to see Customer.io-specific events.
We also support semantic events for other kinds of destinations. See [Semantic Events for other destinations](#semantic-events-for-other-destinations) below for more information.
| Event Name | Description |
|------|--------|
| `Device Created or Updated` | Adds or updates a mobile device (by token), and associates it with a person |
| `Device Deleted` | Deletes a device |
| `User Deleted` | Removes a person from your workspace |
| `User Suppressed` | Removes a person from your workspace and suppresses their identifiers so you can''t add them back to Customer.io. |
| `User Unsuppressed` | Unsuppresses an identifier so you can add someone back to Customer.io and message them again. |
| `Relationship Deleted` | Remove a relationship between a person and an object|
| `Object Deleted` | Remove an object (like an account or company) from your Customer.io workspace|
| `Report Delivery Event` | Report delivery events for messages|
## Semantic events for other destinations
In addition to events that have special meanings [in Customer.io](#customerio-semantic-events), we have a number of other events that we support across different kinds of destinations. These uniform events ensure that we''ll map event data to destinations consistently—so you can move from one provider to another without having to change your event names or payload structures.
For example, our ecommerce events work across any ecommerce platform we integrate with—even if those ecommerce platforms have different APIs or payload structures.
See [Semantic Events](/integrations/data-in/semantic-events/getting-started/) to learn more.
* [A/B Test](/integrations/api/cdp/ab-test/)
* [Ecommerce](/integrations/api/cdp/ecommerce/)
* [Email](/integrations/api/cdp/email/)
* [Live Chat](/integrations/api/cdp/live-chat/)
* [Mobile App](/integrations/api/cdp/mobile-app/)
* [Video](/integrations/api/cdp/video/)
## Backfilling data
By default, Customer.io records a `timestamp` when we receive requests. If you''re sending data to Customer.io in real time, you don''t need to worry about the timestamp.
If you want to backfill requests, you can send a `timestamp`—an ISO 8601 date-time string—telling us when the request occurred. This provides a way to log `track` and `page` calls when the activities _actually_ took place.
'
servers:
- url: https://cdp.customer.io/v1
description: The base URL for all Data Pipelines calls in our United States (US) region.
- url: https://cdp-eu.customer.io/v1
description: The base URL for all Data Pipelines calls in our European Union (EU) region.
tags:
- name: Track
paths:
/track:
post:
operationId: track
summary: Track events
description: 'Send an event associated with a person. The `track` call is how you record the things that people do on your website or in your app.
While this endpoint takes any `event` name you want to send, Customer.io also supports "semantic events." These are specific `event` names (like `User Deleted` or `Device Created or Updated`) that perform special operations in Customer.io like deleting people, adding mobile devices to profiles, and so on. See the [Customer.io Semantic Events documentation](/integrations/api/cdp/customerio/) for complete schemas and examples.
**When you use our libraries, you''ll typically only provide an `event`, an ID for the person, and `properties`. The libraries fill in the rest of the payload automatically.**
'
servers:
- url: https://cdp.customer.io/v1
description: This is a Data Pipeline API.
security:
- Basic-Auth: []
parameters:
- name: X-Strict-Mode
in: header
description: 'When set to `1`, enables strict validation that returns proper HTTP error codes (400/401) for validation failures. When not set or set to any other value, the API operates in permissive mode, logging errors but returning HTTP 200. [Learn more](/integrations/api/track-vs-cdp-api#pipelines-strict-mode)
'
required: false
schema:
type: string
enum:
- '1'
example: '1'
requestBody:
content:
application/json:
schema:
$ref: '#/components/schemas/track'
x-codeSamples:
- lang: json
label: JSON
source: "{\n \"anonymousId\": \"23adfd82-aa0f-45a7-a756-24f2a7a4c895\",\n \"context\": {\n \"library\": {\n \"name\": \"analytics.js\",\n \"version\": \"2.11.1\"\n },\n \"page\": {\n \"path\": \"/\",\n \"referrer\": \"https://www.google.com/\",\n \"search\": \"?q=analytics\",\n \"title\": \"Customer.io Docs\",\n \"url\": \"https://docs.customer.io\"\n },\n \"userAgent\": \"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_0) AppleWebKit/537.36 (KHTML like Gecko) Chrome/46.0.2490.86 Safari/537.36\",\n \"ip\": \"108.0.78.21\"\n },\n \"event\": \"Course Started\",\n \"integrations\": null,\n \"messageId\": \"ajs-f8ca1e4de5024d9430b3928bd8ac6b96\",\n \"properties\": {\n \"title\": \"Intro to Customer.io\"\n },\n \"receivedAt\": \"2015-12-12T19:11:01.266Z\",\n \"sentAt\": \"2015-12-12T19:11:01.169Z\",\n \"timestamp\": \"2015-12-12T19:11:01.249Z\",\n \"type\": \"track\",\n \"userId\": \"AiUGstSDIg\",\n \"originalTimestamp\": \"2015-12-12T19:11:01.152Z\"\n}"
- label: Curl
lang: shell
source: "curl --request POST \\\n --url https://cdp.customer.io/v1/track \\\n -u api_key: \\\n -H 'content-type: application/json' \\\n --data-raw '\n {\n \"userId\": \"97980cfea0067\",\n \"event\": \"Course Started\",\n \"properties\": {\n \"title\": \"Intro to Customer.io\"\n }\n }'\n"
- label: JavaScript (SDK)
lang: javascript
source: "analytics.track(\"video_watched\", {\n video_name: \"Cool New Video\"\n length: 1.56\n speed: 1.25\n finished: false\n});\n"
- label: Node.js (SDK)
lang: javascript
source: "analytics.track({\n userId: '019mr8mf4r',\n event: 'added_to_cart',\n properties: {\n product: \"shoes\",\n revenue: 39.95,\n qty: 1,\n size: 9\n }\n});\n"
- label: Python (SDK)
lang: python
source: "analytics.track('f4ca124298', 'class_started', {\n title: 'How to use Customer.io',\n progress: '2%',\n category: 'getting started'\n})\n"
- label: Go (SDK)
lang: go
source: "client.Enqueue(analytics.Track{\n UserId: \"f4ca124298\",\n Event: \"added_to_cart\",\n Properties: analytics.NewProperties().\n Set(\"product\", \"shoes\"),\n Set(\"price\", 39.95),\n})\n"
responses:
'200':
$ref: '#/components/responses/200'
tags:
- Track
components:
schemas:
all_common_fields:
x-scalar-ignore: true
allOf:
- $ref: '#/components/schemas/common_fields'
- type: object
properties:
context:
description: A dictionary of context about a source call/event, like the user’s IP address or locale. Context is automatically collected by our source libraries.
oneOf:
- $ref: '#/components/schemas/context_non_mobile'
- $ref: '#/components/schemas/context_mobile'
context_page:
x-scalar-ignore: true
type: object
description: Contains information about the current page in the browser. This is automatically collected by our JavaScript source.
properties:
name:
type: string
description: 'The name of the page. Reserved for future use.
'
path:
type: string
description: The path portion of the page's URL. Equivalent to the canonical `path` which defaults to `location.pathname` from the DOM API.
referrer:
type: string
description: The previous page's full URL. Equivalent to `document.referrer` from the DOM API.
search:
type: string
description: The query string portion of the page's URL. Equivalent to `location.search` from the DOM API.
title:
type: string
description: The page's title. Equivalent to `document.title` from the DOM API.
url:
type: string
description: A page's full URL. We first look for the canonical URL. If the canonical URL is not provided, we'll use `location.href` from the DOM API.
keywords:
type: array
description: A list/array of keywords describing the page's content. The keywords are likely the same as, or similar to, the keywords you would find in an HTML `meta` tag for SEO purposes. This property is mainly used by content publishers that rely heavily on pageview tracking. This isn't automatically collected.
items:
type: string
delete_device:
x-scalar-ignore: true
title: Delete Device
description: Delete a device.
type: object
required:
- event
- userId
- context
properties:
event:
type: string
enum:
- Device Deleted
userId:
type: string
context:
type: object
required:
- device
properties:
device:
type: object
required:
- token
properties:
token:
type: string
type:
type: string
enum:
- ios
- android
context_mobile:
x-scalar-ignore: true
description: A dictionary of context about a source call/event, like the user’s IP address or locale. Context is automatically collected by our source libraries.
title: Mobile
allOf:
- $ref: '#/components/schemas/context_common'
- type: object
description: Fields included in events from mobile libraries.
properties:
app:
type: object
description: 'Contains information about the mobile app the event originated from, automatically collected by our mobile libraries when possible.
'
properties:
name:
type: string
description: The name of the app.
version:
type: string
description: The version of the app the call originated from.
build:
type: string
description: The specific build number in the app.
namespace:
type: string
description: The app's namespace.
device:
type: object
description: 'Contains information about the device the event originated from.
'
properties:
id:
type: string
description: The device ID.
advertisingId:
type: string
description: The advertising ID is a unique, anonymous ID for advertising.
manufacturer:
type: string
description: The device manufacturer.
model:
type: string
description: The device model.
name:
type: string
description: The device name.
type:
type: string
description: The device type—android, iOS, etc.
enum:
- android
- ios
version:
type: string
description: The firmware version for the device.
network:
type: object
description: Information about the current network connection, containing `bluetooth`, `carrier`, `cellular`, and `wifi`. If the `context.network.cellular` and `context.network.wifi` fields are empty, then the user is offline.
properties:
bluetooth:
type: boolean
description: Lets you know if bluetooth is enabled on a device.
carrier:
type: string
description: The cellular carrier the phone uses.
cellular:
type: boolean
description: Indicates whether the device's cellular connection is enabled or not.
wifi:
type: boolean
description: Indicates whether a device's wifi connection is enabled or not.
os:
type: object
description: 'Dictionary of information about the operating system, containing `name` and `version`.
'
properties:
name:
type: string
description: The operating system running on the device.
version:
type: string
description: The version of the OS running on the device.
integrations:
x-scalar-ignore: true
type: object
description: 'Contains a list of booleans indicating the integrations that are enabled (true) or disabled (false). By default, all integrations are enabled (returning an empty object). Set `"All": false` to reverse this behavior.
'
additionalProperties:
type: boolean
x-additionalPropertiesName: Enabled/Disabled integrations
example:
All: true
Salesforce: false
unsuppress_person:
x-scalar-ignore: true
title: Unsuppress Person
description: Allow a userId to be added back to your Customer.io workspace.
type: object
required:
- event
- userId
properties:
event:
type: string
enum:
- User Unsuppressed
userId:
type: string
timestamp:
type: string
format: date-time
properties:
type: object
context_non_mobile:
x-scalar-ignore: true
description: A dictionary of context about a source call/event, like the user’s IP address or locale. Context is automatically collected by our source libraries.
title: Non-mobile
allOf:
- $ref: '#/components/schemas/context_common'
- type: object
properties:
campaign:
type: object
description: 'Contains information about the campaign that resulted in the API call, gathered from, or mapping to, UTM parameters (e.g. `utm_source`).
'
properties:
name:
type: string
description: The campaign name.
source:
type: string
description: The source of traffic—like the name of your email list, Facebook, Google, etc.
medium:
type: string
description: The type of traffic a person/event originates from, like `email`, or `referral`.
term:
type: string
description: The keyword term(s) a user came from.
content:
type: string
additionalProperties:
type: string
x-additionalPropertiesName: Additional UTM Parameters
page:
$ref: '#/components/schemas/context_page'
report_delivery_event:
x-scalar-ignore: true
title: Report Delivery Event
description: Reports delivery events for messages.
type: object
required:
- event
- properties
properties:
event:
type: string
enum:
- Report Delivery Event
timestamp:
type: string
format: date-time
properties:
type: object
properties:
deliveryId:
type: string
metric:
type: string
enum:
- delivered
- clicked
- converted
- opened
recipient:
type: string
reason:
type: string
actionValue:
type: string
href:
type: string
create_update_device:
x-scalar-ignore: true
title: Create or Update Device
description: Add or update a device. If a device (represented by `device.token`) exists, does not exist, we'll create it. If the device token already exists, we'll update the it.
type: object
required:
- event
- userId
- context
properties:
event:
type: string
description: The event name.
enum:
- Device Created or Updated
userId:
type: string
description: The user's unique identifier.
context:
type: object
required:
- device
description: Information about the device performing the event.
properties:
device:
type: object
required:
- token
properties:
token:
type: string
description: The device token.
type:
type: string
description: The device type.
enum:
- ios
- android
track:
x-scalar-ignore: true
oneOf:
- title: Custom event
oneOf:
- title: Known User
allOf:
- type: object
required:
- userId
- event
- type
properties:
userId:
$ref: '#/components/schemas/userId'
type:
type: string
enum:
- track
description: The event type. This is set automatically by the request method/endpoint.
event:
type: string
description: The name of the event
example: new_account
properties:
type: object
description: Additional properties for your event.
additionalProperties:
x-additionalPropertiesName: Event Properties
description: Additional properties that you want to capture in the event. These can take any JSON shape.
- $ref: '#/components/schemas/all_common_fields'
- title: Anonymous User
allOf:
- type: object
required:
- event
- type
- anonymousId
properties:
anonymousId:
$ref: '#/components/schemas/anonymousId'
type:
type: string
enum:
- track
description: The event type. This is set automatically by the request method/endpoint.
event:
type: string
description: The name of the event
example: new_account
properties:
type: object
description: Additional properties for your event.
additionalProperties:
x-additionalPropertiesName: Event Properties
description: Additional properties that you want to capture in the event. These can take any JSON shape.
- $ref: '#/components/schemas/all_common_fields'
- title: Group
allOf:
- type: object
required:
- event
- type
- groupId
properties:
groupId:
type: string
description: The ID of the group you want to attribute an event to. Note that not all destinations allow groups (or their downstream equivalent) to perform groups.
type:
type: string
enum:
- track
description: The event type. This is set automatically by the request method/endpoint.
event:
type: string
description: The name of the event
example: new_account
properties:
type: object
description: Additional properties for your event.
additionalProperties:
x-additionalPropertiesName: Event Properties
description: Additional properties that you want to capture in the event. These can take any JSON shape.
- $ref: '#/components/schemas/all_common_fields'
- $ref: '#/components/schemas/create_update_device'
- $ref: '#/components/schemas/delete_device'
- $ref: '#/components/schemas/delete_person'
- $ref: '#/components/schemas/relationship_deleted'
- $ref: '#/components/schemas/group_deleted'
- $ref: '#/components/schemas/suppress_person'
- $ref: '#/components/schemas/unsuppress_person'
- $ref: '#/components/schemas/report_delivery_event'
- $ref: '#/components/schemas/report_content_event'
example:
anonymousId: 23adfd82-aa0f-45a7-a756-24f2a7a4c895
context:
library:
name: analytics.js
version: 2.11.1
page:
path: /
referrer: https://www.google.com/
search: ?q=analytics
title: Customer.io Docs
url: https://docs.customer.io
userAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_0) AppleWebKit/537.36 (KHTML like Gecko) Chrome/46.0.2490.86 Safari/537.36
ip: 108.0.78.21
event: Course Started
integrations: null
messageId: ajs-f8ca1e4de5024d9430b3928bd8ac6b96
properties:
title: Intro to Customer.io
receivedAt: '2015-12-12T19:11:01.266Z'
sentAt: '2015-12-12T19:11:01.169Z'
timestamp: '2015-12-12T19:11:01.249Z'
type: track
userId: AiUGstSDIg
originalTimestamp: '2015-12-12T19:11:01.152Z'
anonymousId:
x-scalar-ignore: true
type: string
description: A unique substitute for a User ID in cases when you don’t have an absolutely unique identifier. Our libraries generate this value automatically to help you track people before they sign up, log in, provide their email, etc.
example: c0e5cae6-6f04-46e4-97a8-25076e8bdc0b
delete_person:
x-scalar-ignore: true
title: Delete Person
description: Remove a person from your Customer.io environment.
type: object
required:
- event
- userId
properties:
event:
type: string
enum:
- User Deleted
userId:
type: string
properties:
type: object
context_common:
x-scalar-ignore: true
type: object
description: Contains contextual information about the event.
properties:
active:
type: boolean
description: 'Whether a user is active.
This is usually used when you send an .identify() call to update the traits independently of when you''ve “last seen” a user.
'
ip:
type: string
description: The user's IP address. This isn't captured by our libraries, but by our servers when we receive client-side events (like from our JavaScript source).
locale:
type: string
description: The locale string for the current user, e.g. `en-US`.
userAgent:
type: string
description: The user agent of the device making the request
channel:
type: string
enum:
- browser
- server
- mobile
description: The channel the event originated from.
relationship_deleted:
x-scalar-ignore: true
title: Delete Relationship
description: Remove a relationship between a person and an object in Customer.io.
type: object
required:
- event
- userId
- properties
properties:
event:
type: string
enum:
- Relationship Deleted
userId:
type: string
properties:
type: object
required:
- objectId
properties:
objectId:
type: string
objectTypeId:
type: integer
default: 1
userId:
x-scalar-ignore: true
type: string
description: The unique identifier for a person. This value should be unique across systems, so you recognize the same person in your sources _and_ destinations.
example: 241ma8mf4a
group_deleted:
x-scalar-ignore: true
title: Delete Object
description: Remove a group (also called an "object") from Customer.io Journeys.
type: object
required:
- event
- anonymousId
- properties
properties:
event:
type: string
enum:
- Object Deleted
anonymousId:
type: string
properties:
type: object
properties:
objectId:
type: string
objectTypeId:
type: integer
default: 1
report_content_event:
x-scalar-ignore: true
title: Report Content Event
description: Reports impressions and clicks for anonymous messages.
type: object
required:
- event
- properties
properties:
event:
type: string
enum:
- Report Content Event
timestamp:
type: string
format: date-time
properties:
type: object
required:
- activityType
properties:
actionType:
type: string
enum:
- viewed_content
- clicked_content
contentId:
type: integer
templateId:
type: integer
suppress_person:
x-scalar-ignore: true
title: Suppress Person
description: Remove a person from your Customer.io workspace and prevent them from being added back.
type: object
required:
- event
- userId
properties:
event:
type: string
enum:
- User Suppressed
userId:
type: string
timestamp:
type: string
format: date-time
properties:
type: object
common_fields:
x-scalar-ignore: true
type: object
properties:
integrations:
$ref: '#/components/schemas/integrations'
messageId:
type: string
description: A unique identifier for a Data Pipelines call, ensuring that each individual event is unique. This is set by Customer.io
receivedAt:
type: string
format:
# --- truncated at 32 KB (33 KB total) ---
# Full source: https://raw.githubusercontent.com/api-evangelist/customer-io/refs/heads/main/openapi/customer-io-track-api-openapi.yml