Knock

API

Notification workflow API for email, SMS, push, in-app and chat

Price: Free tier, then paid
Access: Secret API key

About

Knock is a hosted notification engine. You design cross-channel workflows in a dashboard and trigger them from your backend with one API call. It handles batching, delays, user preferences and in-app feeds, while delivery goes through the channel providers you connect.

What you can do with it

Trigger cross-channel notification workflows from your backend
Add an in-app notification feed and preference center with React components
Batch, delay and throttle notifications per user

Get started

Create a workflow with a channel step in the dashboard
Copy the secret API key for your environment

Example

curl -X POST https://api.knock.app/v1/workflows/welcome/trigger \
  -H "Authorization: Bearer $KNOCK_SECRET_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"recipients":["dr_grant"],"data":{"message":"Life finds a way"}}'

Details

Hosting: Hosted service
Available in: Worldwide
Official SDKs: JavaScript/TypeScript, Python, Ruby, Go, Java, C#, Elixir, PHP, Swift, Kotlin, Dart
MCP server: Remote