Comparing
Async http client/server framework (asyncio)
FastAPI framework, high performance, easy to learn, fast to code, ready for production
| Metric | aiohttp | fastapi |
|---|---|---|
| Ecosystem | Python | Python |
| Difficulty | Beginner | Beginner |
| Weekly downloads | 0 | 0↑ |
| Latest version | v3.13.5 | v0.135.2 |
| Recipes | 1 | 1 |
aiohttp only
Shared
fastapi only
Use aiohttp when you need a battle-tested async HTTP client or server, especially in applications that make many concurrent HTTP calls (scrapers, API aggregators) or build lightweight async web services. It has a mature ecosystem and is widely used in production.
Use FastAPI when building REST or GraphQL APIs in Python, especially when you need async support, automatic OpenAPI/Swagger docs, request validation, or are building microservices. It's the best choice for new Python API projects.
For new async API projects, FastAPI (built on Starlette/uvicorn) has better developer ergonomics, automatic validation, and docs. For synchronous scripts, requests is simpler. httpx offers a compatible API with both sync and async modes if you want flexibility.
FastAPI is API-only — it has no templating, admin interface, or ORM. For full-stack web apps with server-rendered HTML, Django is better. For tiny internal tools, Flask's smaller learning curve might be preferable.
aiohttp
fastapi