head to head · open source
one-api vs OpenAPI-Specification
one-api has 37,316 GitHub stars, 6,887 forks, 1,036 open issues and last shipped 10 months ago. OpenAPI-Specification has 31,291 stars, 9,145 forks, 80 open issues and last shipped 12 days ago. one-api leads on adoption by 19% (37,316 vs 31,291 stars). one-api is written in JavaScript under MIT; OpenAPI-Specification is written in Markdown under Apache-2.0. one-api has attracted 18% as many forks as stars, OpenAPI-Specification 29%. OpenAPI-Specification 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 | OpenAPI-Specification | |
|---|---|---|
| GitHub stars | ★ 37K | ★ 31K |
| License | MIT | Apache-2.0 |
| Written in | JavaScript | Markdown |
| Last push | 2026-01-09 | 2026-10-22 |
| Forks | ⑂ 6.9K | ⑂ 9.1K |
| 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 OpenAPI-Specification if
- You want the OpenAPI-Specification feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Markdown
- You evaluated both and OpenAPI-Specification 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 OpenAPI-Specification
The OpenAPI Specification The OpenAPI Specification is a community driven open specification within the OpenAPI Initiative, a Linux Foundation Collaborative Project. The OpenAPI Specification (OAS) defines a standard, programming language agnostic interface description for HTTP APIs. This allows both humans and computers to discover and understand the capabilities of a service without requiring access to source code, additional documentation, or inspection of network traffic. When properly defined via OpenAPI, a consumer can understand and interact with the remote service with a minimal amount of implementation…
read the full OpenAPI-Specification overview →
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Frequently asked questions
Is one-api or OpenAPI-Specification more popular?
one-api has 37,316 GitHub stars and OpenAPI-Specification has 31,291. one-api has the larger community by that measure.
Are one-api and OpenAPI-Specification free?
Both are open source. one-api is licensed under MIT and OpenAPI-Specification under Apache-2.0. Neither carries a licence fee.
What is the difference between one-api and OpenAPI-Specification?
one-api is written in JavaScript and OpenAPI-Specification in Markdown. 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 OpenAPI-Specification?
Choose one-api if you want the larger community (37,316 stars) or its MIT licence terms. Choose OpenAPI-Specification if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.