head to head · open source
Insomnia vs Scalar
Insomnia has 40,021 GitHub stars, 2,365 forks, 874 open issues and last shipped yesterday. Scalar has 16,136 stars, 937 forks, 68 open issues and last shipped yesterday. Insomnia leads on adoption by 148% (40,021 vs 16,136 stars). Insomnia is written in TypeScript under Apache-2.0; Scalar is written in TypeScript under MIT. Insomnia has attracted 6% as many forks as stars, Scalar 6%. Scalar was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 4 topic tags (api, api-client, http-client, rest-api), so they are genuine substitutes rather than adjacent tools.
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 | Scalar | |
|---|---|---|
| GitHub stars | ★ 40K | ★ 16K |
| License | Apache-2.0 | MIT |
| Written in | TypeScript | TypeScript |
| Last push | 2026-09-17 | 2026-09-17 |
| Forks | ⑂ 2.4K | ⑂ 937 |
| 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 Scalar if
- You want the Scalar feature set and don't need the biggest community
- You prefer the MIT license terms
- Your stack matches TypeScript
- You evaluated both and Scalar fits your workflow better
About Insomnia
Insomnia is an open source, cross platform API client built with Electron and TypeScript for developing and testing APIs across multiple protocols including REST, GraphQL, WebSockets, SSE, and gRPC. It runs on macOS, Windows, and Linux and is distributed under the Apache 2.0 license. The project serves as a direct open source alternative to Postman, offering similar core functionality without vendor lock in or mandatory cloud usage.
read the full Insomnia overview →
About Scalar
Scalar is open source API documentation and testing platform. It lives in TypeScript ecosystem, with Vue in topics, and targets REST API, OpenAPI, Swagger, API client, docs, http client, reference work. License is MIT. It gives interactive API reference from OpenAPI/Swagger documents, plus built in API testing tool. It also gives offline first API client built for OpenAPI.
read the full Scalar overview →
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Frequently asked questions
Is Insomnia or Scalar more popular?
Insomnia has 40,021 GitHub stars and Scalar has 16,136. Insomnia has the larger community by that measure.
Are Insomnia and Scalar free?
Both are open source. Insomnia is licensed under Apache-2.0 and Scalar under MIT. Neither carries a licence fee.
What is the difference between Insomnia and Scalar?
Insomnia is written in TypeScript and Scalar in TypeScript. 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 Scalar?
Choose Insomnia if you want the larger community (40,021 stars) or its Apache-2.0 licence terms. Choose Scalar if its feature set, stack or MIT licence fits better. Both are self-hostable.