head to head · open source
one-api vs NSwag
one-api has 37,316 GitHub stars, 6,887 forks, 1,036 open issues and last shipped 10 months ago. NSwag has 7,369 stars, 1,363 forks, 2,057 open issues and last shipped 2 months ago. one-api leads on adoption by 406% (37,316 vs 7,369 stars). one-api is written in JavaScript under MIT; NSwag is written in C# under MIT. one-api has attracted 18% as many forks as stars, NSwag 18%. NSwag 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
| one-api | NSwag | |
|---|---|---|
| GitHub stars | ★ 37K | ★ 7.4K |
| License | MIT | MIT |
| Written in | JavaScript | C# |
| Last push | 2026-01-09 | 2026-09-07 |
| Forks | ⑂ 6.9K | ⑂ 1.4K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick one-api if
- You weight community size — 37K stars and counting
- You want the MIT license terms
- Your stack matches JavaScript
- 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 one-api
中文 English 日本語 One API ✨ 通过标准的 OpenAI API 格式访问所有的大模型，开箱即用 ✨ 部署教程 · 使用方法 · 意见反馈 · 截图展示 · 在线演示 · 常见问题 · 相关项目 · 赞赏支持 [!NOTE] 本项目为开源项目，使用者必须在遵循 OpenAI 的使用条款以及 法律法规 的情况下使用，不得用于非法用途。 根据《生成式人工智能服务管理暂行办法》的要求，请勿对中国地区公众提供一切未经备案的生成式人工智能服务。 [!NOTE] 稳定版 / 预览版镜像地址：justsong/one api 或者 ghcr.io/songquanpeng/one api alpha 版镜像地址：justsong/one api alpha 或者 ghcr.io/songquanpeng/one api alpha [!WARNING] 使用 root 用户初次登录系统后，务必修改默认密码 123456 ！ 功能 1. 支持多种大模型： + [x] OpenAI ChatGPT 系列模型（支持 Azure OpenAI API） + [x] Anthropic Claude 系列模型 (支持 AWS Claude) + [x] Google PaLM2/Gemini 系列模型 + [x] Mistral 系列模型 + [x] 字节跳动豆包大模型（火山引擎） + [x] 百度文心一言系列模型 +…
read the full one-api 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 one-api or NSwag more popular?
one-api has 37,316 GitHub stars and NSwag has 7,369. one-api has the larger community by that measure.
Are one-api and NSwag free?
Both are open source. one-api is licensed under MIT and NSwag under MIT. Neither carries a licence fee.
What is the difference between one-api and NSwag?
one-api is written in JavaScript 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, one-api or NSwag?
Choose one-api if you want the larger community (37,316 stars) or its MIT licence terms. Choose NSwag if its feature set, stack or MIT licence fits better. Both are self-hostable.