What is Insomnia used for?

Insomnia is a cross-platform API client from Kong for designing, debugging, testing and mocking REST, GraphQL, gRPC, WebSocket and SSE APIs, with local, Git or cloud storage. It is a good fit for debugging APIs during development, designing OpenAPI specs with a team and running API tests in CI pipelines.

Is Insomnia open source?

Yes. Insomnia is open source under the Apache-2.0 licence. Its source code is on GitHub at Kong/insomnia and is written mainly in TypeScript.

Yes. Insomnia is open source, so the software itself is free to use. A managed cloud version is also available, with paid plans from $12 per seat per month.

What is Insomnia an alternative to?

Insomnia is an open-source alternative to Postman, Apidog, Thunder Client and Apifox. Other open-source alternatives to Postman include Bruno, Voiden and Hoppscotch.

Is Insomnia actively maintained?

Yes. The most recent commit to Insomnia was on 2 October 2026. The project has 40k stars on GitHub.

Insomnia: open-source alternative to Postman, Apidog

About Insomnia

Insomnia is an API client from Kong that is open source and runs on every major desktop platform. It handles GraphQL, REST, WebSockets, Server-Sent Events, gRPC and other HTTP-compatible protocols, so one desktop app can cover most of the API work a developer does day to day.

With it you can debug requests, design APIs in a native OpenAPI editor with visual preview, test them with native test suites and a collection runner, and mock them with a cloud or self-hosted mock server. A command line tool supports linting and testing in CI/CD pipelines, collaboration features help teams share work, and third-party plugins extend the app. Projects can be stored in a Local Vault for fully local use, synced through any Git repository, or kept in the cloud with optional end-to-end encryption.

Insomnia is Apache-2.0 licensed and written in TypeScript on Electron. It is free to get started with, and paid collaboration features are available from the vendor. It is a popular alternative to Postman for developers who want flexible storage options.

Key features

REST, GraphQL, gRPC, WebSocket and SSE support
OpenAPI design editor with visual preview
Test suites and collection runner
Mock servers, cloud or self-hosted
CLI for CI/CD linting and testing
Local Vault, Git Sync or Cloud Sync storage

Good fit for

→Debugging APIs during development
→Designing OpenAPI specs with a team
→Running API tests in CI pipelines

Built with: TypeScript; GraphQL
Tags: api-client; api-testing; rest; graphql; grpc; openapi; postman-alternative; developer-tools

Insomnia: questions and answers

What is Insomnia used for?: Insomnia is a cross-platform API client from Kong for designing, debugging, testing and mocking REST, GraphQL, gRPC, WebSocket and SSE APIs, with local, Git or cloud storage. It is a good fit for debugging APIs during development, designing OpenAPI specs with a team and running API tests in CI pipelines.
Is Insomnia open source?: Yes. Insomnia is open source under the Apache-2.0 licence. Its source code is on GitHub at Kong/insomnia and is written mainly in TypeScript.
Is Insomnia free?: Yes. Insomnia is open source, so the software itself is free to use. A managed cloud version is also available, with paid plans from $12 per seat per month.
What is Insomnia an alternative to?: Insomnia is an open-source alternative to Postman, Apidog, Thunder Client and Apifox. Other open-source alternatives to Postman include Bruno, Voiden and Hoppscotch.
Is Insomnia actively maintained?: Yes. The most recent commit to Insomnia was on 2 October 2026. The project has 40k stars on GitHub.