Insomnia
The open-source, collaborative API development platform
Founded
2016
Starting Price
\u00240
Category
Developer Tools
Last updated March 8, 2026
About Insomnia
Insomnia is an open-source, cross-platform API client by Kong for designing, debugging, and testing REST, GraphQL, gRPC, WebSocket, SSE, and SOAP APIs. It features native OpenAPI editing, AI-powered mock server generation, MCP client support, and flexible storage options including local, Git, and cloud sync.
Pros & Cons
Pros
- Clean, intuitive UI that's easy to navigate without feeling cluttered
- Excellent GraphQL support with automatic schema introspection and intelligent autocomplete
- Open-source core under MIT license with all essential features free
- Lightweight and fast — launches quickly and uses less memory than alternatives
- Flexible storage options: local, Git, or cloud sync with end-to-end encryption
Key Features
Multi-Protocol API Client
Send HTTP, REST, gRPC, GraphQL, WebSocket, SOAP, and SSE requests from a single unified interface
OpenAPI Design & Validation
Native OpenAPI editor with real-time linting, visual preview, and spec validation for API-first development
API Mocking
Generate instant mock servers with AI-powered responses, available locally or in the cloud
Git Sync
Sync API collections and design specs with Git repositories for version control and team collaboration
MCP Client Support
Test and debug Model Context Protocol (MCP) servers directly within Insomnia
Automated Testing
Native test suites and collection runner for automated API validation with Inso CLI for CI/CD pipelines
Plugin Ecosystem
Open-source plugin architecture with 350+ community-built plugins for extensibility
Pricing
Essentials
\u00240
- Unlimited Git Sync projects (up to 3 users)
- Unlimited Cloud/Local projects
- Inso CLI access
- Unlimited collection runs & environments
- 1,000 mock server requests/month
Best For
API Development & Debugging
Quickly build, test, and debug REST, GraphQL, and gRPC APIs with an intuitive desktop client
API-First Design
Design APIs using the native OpenAPI editor with real-time validation before writing any code
CI/CD Pipeline Integration
Automate API testing in continuous integration pipelines using the Inso CLI tool
MCP Server Testing
Test and debug Model Context Protocol servers for AI agent integrations
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