Learn how to use Courier REST API to send and manage multichannel transactional and lifecycle notifications across email, SMS, push, Slack, Teams, and in-app—all through one unified API.
The Courier REST API gives developers full control over sending, managing, and tracking notifications across every channel—email, SMS, push, chat, and in-app. With a single, consistent API, you can design powerful workflows that deliver messages where your users are most active.Use the API to send notifications, manage user profiles and preferences, organize audiences, and monitor delivery and engagement data. Courier provides official SDKs so you can integrate in your preferred language — including Node.js, Python, Ruby, Go, Java, PHP, and C# / .NET. You can download any SDK directly from GitHub to get started quickly.Key capabilities:
Send messages through one or many channels with one request
Manage user profiles, preferences, and audience lists
Retrieve message histories and event logs for analytics or debugging
Secure and reliable delivery with API keys, idempotency, and rate limits
