Knock
Customer engagement infrastructure for developers
Founded
2021
Starting Price
$0
Category
Communication
Last updated April 27, 2026
About Knock
Knock is a notification infrastructure platform that helps engineering teams build and manage cross-channel product notifications. It provides APIs and a visual workflow builder to send messages across email, SMS, push, chat, and in-app channels without building complex notification systems from scratch.
Pros & Cons
Pros
- Developer-friendly API with excellent documentation and SDKs
- Visual workflow builder accessible to both engineers and non-technical teams
- Supports all major notification channels from a single platform
- Built-in preference management reduces engineering overhead
- Multiple environments with incremental change promotion feels like a proper engineering workflow
Key Features
Cross-Channel Notifications
Send messages across email, SMS, push, in-app, and chat channels from a single API
Visual Workflow Builder
Drag-and-drop editor to design notification workflows with branching, delays, and batching
In-App Notification Feed
Pre-built, customizable in-app notification feed component with real-time updates
User Preference Management
Let users control where and when they receive notifications across all channels
Template Management
Manage notification templates in a single location with autocomplete and partials support
Cross-Channel Analytics
Stream notification data to external tools and track delivery, open, and click rates
Batch & Digest
Automatically batch multiple notifications into digest summaries to reduce noise
Pricing
Developer
$0
- Up to 10K notifications/month
- All channels (email, SMS, push, in-app, chat)
- Visual workflow builder
- Community support
Starter
$250/month
Best For
SaaS Product Notifications
Send transactional and engagement notifications across channels when users interact with your product
Collaborative Workflows
Notify team members about comments, assignments, and status changes in real-time
E-commerce Order Updates
Keep customers informed about order status, shipping, and delivery across their preferred channels
Developer Platform Alerts
Send build notifications, deployment alerts, and API usage warnings to engineering teams
