Customer.io Track Region API
Determine whether your account and data are hosted in the US or EU data center using your [Track API Key](https://fly.customer.io/settings/api_credentials).
Determine whether your account and data are hosted in the US or EU data center using your [Track API Key](https://fly.customer.io/settings/api_credentials).
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openapi: 3.2.0
info:
version: 1.0.0
title: Customer.io Track Track Region API
description: "# Overview\n\nOur Track API provides ways to send real-time customer data to your Customer.io workspace including customer identification and event tracking.\n\n# Use our Postman collection\n\nWe've generated a Postman collection to help you get started with our APIs.\n\nIf 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.\n\n**NOTE**: Postman endpoints default to our US APIs. If you're in our European (EU) region, you'll need to add `-eu` to the server variables (`track_api_url` and `app_api_url`).\n\n[<img src=\"https://run.pstmn.io/button.svg\" alt=\"Run In Postman\" style=\"width: 128px; height: 32px;\">](https://god.gw.postman.com/run-collection/23697545-0f7ae1e8-8177-46fc-808a-2fd363dd52b9?action=collection%2Ffork&source=rip_markdown&collection-url=entityId%3D23697545-0f7ae1e8-8177-46fc-808a-2fd363dd52b9%26entityType%3Dcollection%26workspaceId%3Db886877f-fc09-475f-84fe-6221a98f4d18#?env%5BCustomer.io%20API%20Environment%5D=W3sia2V5IjoidHJhY2tfYXBpX3VybCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiJ0cmFjay5jdXN0b21lci5pbyIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoiYXBwX2FwaV91cmwiLCJ0eXBlIjoiZGVmYXVsdCIsInZhbHVlIjoiYXBpLmN1c3RvbWVyLmlvIiwiZW5hYmxlZCI6dHJ1ZX0seyJrZXkiOiJzaXRlX2lkIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoiYXBpX2tleSIsInR5cGUiOiJzZWNyZXQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoiYmVhcmVyIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoiYnJvYWRjYXN0X2lkIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoiaW1wb3J0X2lkIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoiZW1haWxfYWRkcmVzcyIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6InN1cHByZXNzaW9uX3R5cGUiLCJ0eXBlIjoiZGVmYXVsdCIsInZhbHVlIjoiIiwiZW5hYmxlZCI6dHJ1ZX0seyJrZXkiOiJjb2xsZWN0aW9uX2lkIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5Ijoic25pcHBldF9uYW1lIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5Ijoid2ViaG9va19pZCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6InNlbmRlcl9pZCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6ImV4cG9ydF9pZCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6Im1lc3NhZ2VfaWQiLCJ0eXBlIjoiZGVmYXVsdCIsInZhbHVlIjoiIiwiZW5hYmxlZCI6dHJ1ZX0seyJrZXkiOiJzZWdtZW50X2lkIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoibmV3c2xldHRlcl9pZCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6ImNvbnRlbnRfaWQiLCJ0eXBlIjoiZGVmYXVsdCIsInZhbHVlIjoiIiwiZW5hYmxlZCI6dHJ1ZX0seyJrZXkiOiJjYW1wYWlnbl9pZCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6ImFjdGlvbl9pZCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6ImN1c3RvbWVyX2lkIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoidHJhbnNhY3Rpb25hbF9pZCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6InRyaWdnZXJfaWQiLCJ0eXBlIjoiZGVmYXVsdCIsInZhbHVlIjoiIiwiZW5hYmxlZCI6dHJ1ZX0seyJrZXkiOiJmb3JtX2lkIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9LHsia2V5IjoiaWRlbnRpZmllciIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6ImRldmljZV9pZCIsInR5cGUiOiJkZWZhdWx0IiwidmFsdWUiOiIiLCJlbmFibGVkIjp0cnVlfSx7ImtleSI6ImRlbGl2ZXJ5X2lkIiwidHlwZSI6ImRlZmF1bHQiLCJ2YWx1ZSI6IiIsImVuYWJsZWQiOnRydWV9XQ==)\n\n# Server addresses: US and EU\nCustomer.io hosts services in the United States (US) and European Union. Select the appropriate server address for your region.\n\n| Region | Server Address |\n| :-- | :-- |\n| US | https://track.customer.io |\n| EU | https://track-eu.customer.io |\n\nNote that if your account is in the EU region and you send traffic to our US endpoints, we'll redirect it accordingly but this traffic still passes through US servers and data could be logged in the US.\n\n# Authentication \n\nYou can find all of your API authentication information in your [Account Settings](https://fly.customer.io/settings/api_credentials). Our Tracking API uses HTTP basic authorization. The App API uses bearer authorization, and you can generate tokens supporting different scopes. Each operation in this document references the authorization header it requires.\n\n# v1 vs v2 APIs\n\nMost of the time, when we talk about *The Track API*, we're talking about the v1 API because the v2 API isn't used in any of our libraries and rarely used in libraries built by third parties; it's much more common that you'd encounter the v1 API.\n\nIf you're integrating with Customer.io using one of our libraries, or a third party customer data platform (CDP) like Segment or Rudderstack, you'll be using the v1 API.\n\nThe v2 API is newer and supports two important features that the v1 API doesn't natively support: objects and batching. But, if you're integrating directly with our API, we suggest you use the [Pipelines API](/integrations/api/cdp/). The Pipelines API supports both objects, batching, *and* all of our newest integrations and libraries are based on it.\n\n# Rate Limits\n\nThe Track API has a rate limit of 1000 requests per second for both active data integrations and historical backfill scripts. This limit applies to both our v1 and v2 APIs. \n\nWhile 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.\n\n**Rate limits are subject to change. We may adjust these thresholds to ensure stable performance for all customers.**\n\nBelow are the payload size limits for the Track API. If any of these limits are too restrictive for your needs, contact support to let us know your situation as we may be able to accommodate special circumstances. \n\n## Customer limits\n\nThese limits apply to people and their attributes, often referred to as \"customers\" in our APIs.\n\n| Data Type | Limit | Description |\n| -- | -- | -- |\n| ID | 150 bytes | Max length of a person's ID value |\n| Attribute Name | 150 bytes | Max length of each attribute name |\n| Attribute Value | 1000 bytes | Max length of attribute values |\n| Unique attributes | 300 | Max number of attributes allowed per person or Identify call |\n\n## Object and relationship limits\n\nObjects (groups) and relationships between people and objects can have their own attributes. Their limits are similar to people (customers).\n\n| Data Type | Limit | Description |\n| -- | -- | -- |\n| Object ID | 150 bytes | Max length of a object's ID |\n| Attribute Names | 150 bytes | Max length of each attribute name |\n| Attribute Values | 1000 bytes | Max length of attribute values |\n| Unique attributes | 300 | Max number of attributes allowed per object or relationship |\n| Total attribute size | 100 Kilobytes | Max size of all attributes associated with an object or relationship |\n\n## Track API Event limits\n\nThese limits apply to events that you'll send with the `/v1/track` call.\n\n| Data Type | Limit | Description |\n| -- | -- | -- |\n| Event Name | 100 bytes | Max length of each event name |\n| Event Data | 100000 bytes | Max length of each event data |\n\n\n## v2 API Limits\n\nThe v2 API has two endpoints, both of which have limits on the total size of requests. \n* `/entity` is limited to requests 32kb or smaller.\n* `/batch` is limited to requests 500kb or smaller.\n \n Each of the requests within a batch must also be 32kb or smaller.\n"
servers:
- url: https://track.customer.io
description: The base URL for the Track API. Track endpoints use basic authentication with your Site ID as the user name and your secret key as the password.
- url: https://track-eu.customer.io
description: The base URL for the Track API (EU region). Track endpoints use basic authentication with your Site ID as the user name and your secret key as the password.
tags:
- name: trackRegion
x-displayName: Account Region
description: 'Determine whether your account and data are hosted in the US or EU data center using your [Track API Key](https://fly.customer.io/settings/api_credentials).
'
paths:
/api/v1/accounts/region:
get:
operationId: getRegion
summary: Find your account region
description: "This endpoint returns the appropriate region and URL for your Track API credentials. Use it to determine the URLs you should use to successfully complete other requests.\n\nYou can perform this operation against either of the track API regional URLs; it returns your region in either case. \n\nThis endpoint also returns an `environment_id`, which represents the workspace the credentials are valid for. \n"
tags:
- trackRegion
security:
- Tracking-API-Key: []
servers:
- url: https://track.customer.io
description: This endpoint is a part of the Track API.
responses:
'200':
description: Your credentials are valid.
content:
application/json:
schema:
type: object
properties:
url:
type: string
description: The URL you will use for future Track API calls.
enum:
- https://track.customer.io
- https://track-eu.customer.io
example: https://track.customer.io
region:
type: string
description: The 'region' that your account is in. While the `url` relates to the Track API, this tells you which region of the Customer.io API to use. If this value is `eu`, you can append the subdomain any of the Customer.io API URLs with `-eu` to route your request to the appropriate region.
enum:
- us
- eu
example: us
environment_id:
type: integer
description: The identifier for the workspace that your credentials grant access to.
example: 3
'401':
$ref: '#/components/responses/401'
components:
responses:
'401':
description: Unauthorized request. Make sure that you provided the right credentials.
securitySchemes:
Tracking-API-Key:
type: http
scheme: basic
description: 'The Track API uses a basic authentication scheme. Your credentials are your **Site ID** and your **API key**, **Base-64 encoded** in the format `site_id:api_key`.
You can find your Site ID and API key on the [Track API Keys page](https://fly.customer.io/settings/api_credentials).
'