Marketing Automation Basic Auth

Customer.io REST API

Automated messaging platform for marketers and developers

Customer.io is a versatile marketing automation platform that enables developers to send targeted emails, push notifications, SMS, and in-app messages based on user behavior and attributes. The API provides comprehensive control over customer data, event tracking, campaign management, and message delivery, making it ideal for building personalized customer engagement workflows. Developers use Customer.io to integrate behavioral messaging into their applications, sync customer data from multiple sources, and create sophisticated multi-channel communication strategies.

Base URL https://track.customer.io/api/v1

API Endpoints

Method	Endpoint	Description
PUT	`/customers/{id}`	Create or update a customer profile with attributes and metadata
DELETE	`/customers/{id}`	Delete a customer and all associated data from your workspace
POST	`/customers/{id}/events`	Track custom events for a customer to trigger campaigns and workflows
POST	`/api/campaigns/{campaign_id}/triggers`	Trigger a campaign for specific customers with custom data
GET	`/api/campaigns`	List all campaigns in your workspace with filtering options
POST	`/api/send/email`	Send a transactional email to a customer using a template
POST	`/api/send/push`	Send a push notification to a customer's registered devices
GET	`/api/customers/{id}/messages`	Retrieve message delivery history for a specific customer
POST	`/customers/{id}/segments/{segment_id}`	Add a customer to a manual segment for targeted messaging
DELETE	`/customers/{id}/segments/{segment_id}`	Remove a customer from a manual segment
GET	`/api/segments`	List all segments in your workspace with membership counts
POST	`/api/v1/merge_customers`	Merge two customer profiles, combining their data and history
POST	`/customers/{id}/suppress`	Suppress a customer from receiving messages across all channels
POST	`/customers/{id}/unsuppress`	Remove suppression status and re-enable messaging for a customer
GET	`/api/exports/customers`	Export customer data in CSV or JSON format for analysis

Code Examples

# Create or update a customer
curl -X PUT https://track.customer.io/api/v1/customers/user123 \
  -u site_id:api_key \
  -H "Content-Type: application/json" \
  -d '{
    "email": "user@example.com",
    "created_at": 1234567890,
    "first_name": "John",
    "plan": "premium"
  }'

# Track a custom event
curl -X POST https://track.customer.io/api/v1/customers/user123/events \
  -u site_id:api_key \
  -H "Content-Type: application/json" \
  -d '{
    "name": "purchase_completed",
    "data": {
      "amount": 99.99,
      "product": "Premium Plan"
    }
  }'

// Create or update a customer
const siteId = 'your_site_id';
const apiKey = 'your_api_key';
const credentials = btoa(`${siteId}:${apiKey}`);

fetch('https://track.customer.io/api/v1/customers/user123', {
  method: 'PUT',
  headers: {
    'Authorization': `Basic ${credentials}`,
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    email: 'user@example.com',
    created_at: Math.floor(Date.now() / 1000),
    first_name: 'John',
    plan: 'premium'
  })
})
.then(response => response.json())
.then(data => console.log(data))
.catch(error => console.error('Error:', error));

// Track a custom event
fetch('https://track.customer.io/api/v1/customers/user123/events', {
  method: 'POST',
  headers: {
    'Authorization': `Basic ${credentials}`,
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    name: 'purchase_completed',
    data: {
      amount: 99.99,
      product: 'Premium Plan'
    }
  })
})
.then(response => response.json())
.then(data => console.log(data))
.catch(error => console.error('Error:', error));

import requests
from requests.auth import HTTPBasicAuth
import time

# Configuration
site_id = 'your_site_id'
api_key = 'your_api_key'
base_url = 'https://track.customer.io/api/v1'

# Create or update a customer
response = requests.put(
    f'{base_url}/customers/user123',
    auth=HTTPBasicAuth(site_id, api_key),
    json={
        'email': 'user@example.com',
        'created_at': int(time.time()),
        'first_name': 'John',
        'plan': 'premium'
    }
)
print(response.status_code)

# Track a custom event
response = requests.post(
    f'{base_url}/customers/user123/events',
    auth=HTTPBasicAuth(site_id, api_key),
    json={
        'name': 'purchase_completed',
        'data': {
            'amount': 99.99,
            'product': 'Premium Plan'
        }
    }
)
print(response.status_code)

# Send a transactional email
response = requests.post(
    'https://api.customer.io/v1/send/email',
    auth=HTTPBasicAuth(site_id, api_key),
    json={
        'transactional_message_id': 1,
        'to': 'user@example.com',
        'identifiers': {'id': 'user123'},
        'message_data': {
            'order_id': 'ORD-12345',
            'total': 99.99
        }
    }
)
print(response.json())

Use Customer.io from Claude / Cursor / ChatGPT

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track_customer_event Track behavioral events for customers to trigger automated campaigns and update customer profiles based on user actions

update_customer_attributes Create or update customer profiles with attributes, preferences, and segmentation data for personalized messaging

send_transactional_message Send transactional emails, SMS, or push notifications with dynamic content based on customer data and events

manage_customer_segments Add or remove customers from segments to control campaign targeting and message delivery

retrieve_message_history Query customer message delivery history, engagement metrics, and campaign performance data for analysis

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Customer.io REST API

API Endpoints

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Code Examples

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