head to head · open source
Insomnia vs NSwag
Insomnia has 40,111 GitHub stars, 2,388 forks, 874 open issues and last shipped yesterday. NSwag has 7,369 stars, 1,363 forks, 2,057 open issues and last shipped 2 months ago. Insomnia leads on adoption by 444% (40,111 vs 7,369 stars). Insomnia is written in TypeScript under Apache-2.0; NSwag is written in C# under MIT. Insomnia has attracted 6% as many forks as stars, NSwag 18%. Insomnia was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Insomnia | NSwag | |
|---|---|---|
| GitHub stars | ★ 40K | ★ 7.4K |
| License | Apache-2.0 | MIT |
| Written in | TypeScript | C# |
| Last push | 2026-11-02 | 2026-09-07 |
| Forks | ⑂ 2.4K | ⑂ 1.4K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Insomnia if
- You weight community size — 40K stars and counting
- You want the Apache-2.0 license terms
- Your stack matches TypeScript
- You value the larger contributor base for long-term maintenance
pick NSwag if
- You want the NSwag feature set and don't need the biggest community
- You prefer the MIT license terms
- Your stack matches C#
- You evaluated both and NSwag fits your workflow better
About Insomnia
Insomnia API Client Insomnia is an open source, cross platform API client for GraphQL, REST, WebSockets, Server Sent Events (SSE), gRPC and any other HTTP compatible protocol. With Insomnia you can: Debug APIs using the most popular protocols and formats. Design APIs using the native OpenAPI editor and visual preview. Test APIs using native test suites and collection runner. Mock APIs using a cloud or self hosted mocking server. Build CI/CD pipelines using the native Insomnia CLI for linting and testing. Collaborate with others using the many collaboration features. And more including the ability to use 3rd…
read the full Insomnia overview →
About NSwag
NSwag: The Swagger/OpenAPI toolchain for .NET, ASP.NET Core and TypeScript NSwag NJsonSchema Apimundo Namotion.Reflection :point right: Announcing Apimundo: An API documentation system based on NSwag and NJsonSchema :point left: NSwag is a Swagger/OpenAPI 2.0 and 3.0 toolchain for .NET, .NET Core, Web API, ASP.NET Core, TypeScript (jQuery, AngularJS, Angular 2+, Aurelia, KnockoutJS and more) and other platforms, written in C . The OpenAPI/Swagger specification uses JSON and JSON Schema to describe a RESTful web API. The NSwag project provides tools to generate OpenAPI specifications from existing ASP.NET Web API…
read the full NSwag overview →
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Frequently asked questions
Is Insomnia or NSwag more popular?
Insomnia has 40,111 GitHub stars and NSwag has 7,369. Insomnia has the larger community by that measure.
Are Insomnia and NSwag free?
Both are open source. Insomnia is licensed under Apache-2.0 and NSwag under MIT. Neither carries a licence fee.
What is the difference between Insomnia and NSwag?
Insomnia is written in TypeScript and NSwag in C#. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Insomnia or NSwag?
Choose Insomnia if you want the larger community (40,111 stars) or its Apache-2.0 licence terms. Choose NSwag if its feature set, stack or MIT licence fits better. Both are self-hostable.