head to head · open source
fastapi vs one-api
fastapi has 102,402 GitHub stars, 9,903 forks, 78 open issues and last shipped 4 days ago. one-api has 36,932 stars, 6,867 forks, 1,036 open issues and last shipped 8 months ago. fastapi leads on adoption by 177% (102,402 vs 36,932 stars). fastapi is written in Python under MIT; one-api is written in JavaScript under MIT. fastapi has attracted 10% as many forks as stars, one-api 19%. fastapi was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 1 topic tag (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
| fastapi | one-api | |
|---|---|---|
| GitHub stars | ★ 102K | ★ 37K |
| License | MIT | MIT |
| Written in | Python | JavaScript |
| Last push | 2026-09-14 | 2026-01-09 |
| Forks | ⑂ 9.9K | ⑂ 6.9K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick fastapi if
- You weight community size — 102K stars and counting
- You want the MIT license terms
- Your stack matches Python
- You value the larger contributor base for long-term maintenance
pick one-api if
- You want the one-api feature set and don't need the biggest community
- You prefer the MIT license terms
- Your stack matches JavaScript
- You evaluated both and one-api fits your workflow better
About fastapi
FastAPI is an MIT licensed, high performance Python web framework for building APIs with standard Python type hints, aimed at Python developers and teams that need production ready HTTP services with automatic OpenAPI documentation.
read the full fastapi overview →
About one-api
One API is a self hosted LLM API management and key redistribution system that exposes many model providers through the standard OpenAI API format, aimed at developers, teams and operators who want a single endpoint, a single key model and a single quota surface across providers.
read the full one-api overview →
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Frequently asked questions
Is fastapi or one-api more popular?
fastapi has 102,402 GitHub stars and one-api has 36,932. fastapi has the larger community by that measure.
Are fastapi and one-api free?
Both are open source. fastapi is licensed under MIT and one-api under MIT. Neither carries a licence fee.
What is the difference between fastapi and one-api?
fastapi is written in Python and one-api in JavaScript. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, fastapi or one-api?
Choose fastapi if you want the larger community (102,402 stars) or its MIT licence terms. Choose one-api if its feature set, stack or MIT licence fits better. Both are self-hostable.