head to head · open source
fastapi vs WebApiClient
fastapi has 102,409 GitHub stars, 9,906 forks, 78 open issues and last shipped 5 days ago. WebApiClient has 2,136 stars, 445 forks, 14 open issues and last shipped 2 months ago. fastapi leads on adoption by 4,694% (102,409 vs 2,136 stars). fastapi is written in Python under MIT; WebApiClient is written in C# under MIT. fastapi has attracted 10% as many forks as stars, WebApiClient 21%. fastapi was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 2 topic tags (json, openapi), 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.
← all 13541 open source comparisons
Side by side
| fastapi | WebApiClient | |
|---|---|---|
| GitHub stars | ★ 102K | ★ 2.1K |
| License | MIT | MIT |
| Written in | Python | C# |
| Last push | 2026-09-14 | 2026-07-17 |
| Forks | ⑂ 9.9K | ⑂ 445 |
| 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 WebApiClient if
- You want the WebApiClient feature set and don't need the biggest community
- You prefer the MIT license terms
- Your stack matches C#
- You evaluated both and WebApiClient 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 WebApiClient
WebApiClient is an MIT licensed C REST API client library for .NET developers who declare HTTP endpoints as interfaces instead of hand writing HttpClient plumbing.
read the full WebApiClient overview →
More in Developer Tools
Related comparisons
More API Development & Testing projects
Compare either of these against the rest of the API Development & Testing field.
Frequently asked questions
Is fastapi or WebApiClient more popular?
fastapi has 102,409 GitHub stars and WebApiClient has 2,136. fastapi has the larger community by that measure.
Are fastapi and WebApiClient free?
Both are open source. fastapi is licensed under MIT and WebApiClient under MIT. Neither carries a licence fee.
What is the difference between fastapi and WebApiClient?
fastapi is written in Python and WebApiClient 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, fastapi or WebApiClient?
Choose fastapi if you want the larger community (102,409 stars) or its MIT licence terms. Choose WebApiClient if its feature set, stack or MIT licence fits better. Both are self-hostable.