# Express vs FastAPI

| Attribute | Express | FastAPI |
|---|---|---|
| **vioscaleAI score** | 75.7 (77% (high)) | 78.1 (69% (medium)) |
| activity.commits_last_30d | 10 | 63 |
| adoption.dependent_repos | 1,853,938 | 43,608 |
| adoption.github_stars | 69,528 | 102,768 |
| adoption.package_downloads_weekly | 168,467,798 | 97,378,207 |
| adoption.stackoverflow_questions | 96,000 | 31,000 |
| content.faq | `[{"answer":"A minimal framework providing essential routing, middleware, and HTTP utilities for building web applications and APIs in Node.js without imposing architectural constraints. It is indexed under Web Frameworks.","source":"https://expressjs.com","question":"What is Express?","confidence":0.6},{"answer":"Express is open source, so it can be self-hosted and used at no licence cost. It is released under the MIT licence. Pricing changes often, so verify at source before relying on it.","source":"https://expressjs.com","question":"Is Express free to use?","confidence":0.6},{"answer":"Express supports the web and a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://expressjs.com","question":"What platforms does Express support?","confidence":0.6},{"answer":"Yes. Express can be deployed cloud / SaaS, on-premise and self-hosted, so it does not have to run on the vendor's infrastructure.","source":"https://expressjs.com","question":"Can Express be self-hosted?","confidence":0.6},{"answer":"We have confirmed 13 integrations for Express, including Cassandra, Couchbase, CouchDB, LevelDB, MySQL, MongoDB, Neo4j and Oracle, plus 5 more. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://expressjs.com","question":"What does Express integrate with?","confidence":0.6},{"answer":"Yes. Express is published under the MIT licence, a permissive licence that generally allows commercial use and modification. Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://github.com/expressjs/express","question":"Is Express open source?","confidence":0.99},{"answer":"Express is available worldwide. Its primary market is the United States. The vendor is headquartered in the United States.","source":"https://expressjs.com","question":"Where is Express available?","confidence":0.95}]` | `[{"answer":"FastAPI is a modern Python framework for building REST APIs and web services. It is built on top of Starlette for web functionality and Pydantic for data validation, combining these components with Python type hints to enable automatic API documentation, data validation, and fast development cycles.","source":"https://fastapi.tiangolo.com","question":"What is FastAPI and what is it primarily used for?","confidence":0.95},{"answer":"FastAPI is a Python framework that relies on Starlette for HTTP handling and async support, and Pydantic for data validation and serialization. It leverages Python's native type hints as a central feature to drive both validation and automatic interactive API documentation generation.","source":"https://fastapi.tiangolo.com","question":"What programming language is FastAPI built on and what are its core dependencies?","confidence":0.95},{"answer":"FastAPI is completely open source and free, distributed under the MIT license with no cost to use or modify. The creators offer an optional commercial service called FastAPI Cloud for managed deployment and hosting, but the core framework incurs no licensing fees.","source":"https://fastapi.tiangolo.com","question":"Is FastAPI open source and what is its pricing model?","confidence":0.95},{"answer":"FastAPI is one of the fastest Python web frameworks, with benchmarks showing performance on par with Node.js and Go-based APIs. This speed stems from its async/await capabilities and reliance on highly optimized underlying libraries like Starlette and Pydantic.","source":"https://fastapi.tiangolo.com","question":"How does FastAPI's performance compare to other Python web frameworks?","confidence":0.92},{"answer":"Uvicorn is the standard ASGI server for FastAPI, run via the fastapi run command or uvicorn CLI. Deployment typically involves running Uvicorn with multiple worker processes for concurrency, containerizing with Docker for cloud platforms, or using managed services that automatically handle scaling and reverse proxying.","source":"https://fastapi.tiangolo.com/deployment/concepts/","question":"What ASGI server should I use to deploy FastAPI, and what are the typical deployment models?","confidence":0.93},{"answer":"FastAPI has built-in support for WebSockets enabling real-time bidirectional communication, Server-Sent Events for server-to-client streaming, and background tasks for asynchronous processing. All of these features are natively integrated without requiring additional extensions.","source":"https://fastapi.tiangolo.com/advanced/","question":"Does FastAPI support real-time communication and asynchronous patterns?","confidence":0.94},{"answer":"FastAPI includes built-in support for OAuth2 with JSON Web Tokens (JWT), HTTP Basic Authentication, password hashing utilities, bearer token validation, and Cross-Origin Resource Sharing (CORS) configuration. These security patterns are designed to be straightforward to implement for common use cases.","source":"https://fastapi.tiangolo.com/advanced/","question":"What authentication and security capabilities does FastAPI provide out of the box?","confidence":0.93},{"answer":"FastAPI integrates with SQL relational databases via standard ORMs, supports form data and file uploads, includes middleware patterns, and can mount alongside WSGI applications like Flask or Django. It also provides Jinja2 template support, dependency injection for complex patterns, and auto-generation of client SDKs from your API.","source":"https://fastapi.tiangolo.com/advanced/","question":"What common integrations and databases does FastAPI support?","confidence":0.92}]` |
| deployment.options | `{"cloud":true,"on_prem":true,"self_hosted":true}` | `{"cloud":true}` |
| description.long | A flexible web framework providing essential features for web applications and APIs while allowing developers to choose their own complementary tools and libraries. | A Python web framework designed for creating APIs with automatic documentation, built on standard protocols and type hints to enable rapid development and deployment. |
| features.capabilities | `{"language":"JavaScript","api_routes":true,"hot_reload":false,"edge_runtime":false,"file_routing":false,"license_type":"MIT/BSD","orm_included":false,"streaming_ssr":false,"language_runtime":"JS/TS","typescript_first":false,"server_components":false,"architecture_style":"minimalist","templating_included":true}` | `{"language":"Python","api_first":true,"api_routes":true,"hot_reload":true,"async_model":"event-loop-async","openapi_autogen":true,"language_runtime":"Python","websocket_support":true,"architecture_style":"structured-di","dependency_injection":true,"background_jobs_included":true,"testing_framework_included":true}` |
| integrations.count | 13 | 11 |
| integrations.list | `[{"name":"Cassandra"},{"name":"Couchbase"},{"name":"CouchDB"},{"name":"LevelDB"},{"name":"MySQL"},{"name":"MongoDB"},{"name":"Neo4j"},{"name":"Oracle"},{"name":"PostgreSQL"},{"name":"Redis"},{"name":"SQL Server"},{"name":"SQLite"},{"name":"Elasticsearch"}]` | `[{"name":"Starlette"},{"name":"Pydantic"},{"name":"OpenAPI"},{"name":"JSON Schema"},{"name":"Swagger UI"},{"name":"ReDoc"},{"name":"OAuth2"},{"name":"JWT"},{"name":"HTTP Basic authentication"},{"name":"Cookies"},{"name":"Session management"}]` |
| language.primary | JavaScript | Python |
| license.spdx | MIT | MIT |
| market.availability | `{"source":"https://expressjs.com","hqCountry":"US","confidence":0.95,"primaryMarkets":["US"],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` | `{"source":"https://fastapi.tiangolo.com","hqCountry":"ES","confidence":0.95,"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` |
| platform.support | `{"cli":true,"web":true}` | `{"cli":true,"web":true}` |
| pricing | `{"type":"open_source","freeTier":true,"sourceUrl":"https://expressjs.com","retrievedAt":"2026-10-05T10:08:30.684Z"}` | `{"type":"open_source","freeTier":true,"sourceUrl":"https://fastapi.tiangolo.com","retrievedAt":"2026-08-14T11:09:42.452Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | open_source | open_source |
| pricing.price_level | free | free |
| pricing.transparent | yes | - |
| release.cadence_days | 4 | 14 |
| release.history | `[{"url":"https://github.com/expressjs/express/releases/tag/v4.22.2","date":"2026-05-11T18:54:02Z","type":"stable","version":"v4.22.2"},{"url":"https://github.com/expressjs/express/releases/tag/v5.2.1","date":"2025-12-01T20:54:44Z","type":"stable","version":"v5.2.1"},{"url":"https://github.com/expressjs/express/releases/tag/v5.2.0","date":"2025-12-01T16:21:03Z","type":"stable","version":"v5.2.0"},{"url":"https://github.com/expressjs/express/releases/tag/v4.22.1","date":"2025-12-01T20:55:45Z","type":"stable","version":"v4.22.1"},{"url":"https://github.com/expressjs/express/releases/tag/4.22.0","date":"2025-12-01T16:19:48Z","type":"stable","version":"4.22.0"},{"url":"https://github.com/expressjs/express/releases/tag/v5.0.1","date":"2024-10-08T19:41:00Z","type":"stable","version":"v5.0.1"},{"url":"https://github.com/expressjs/express/releases/tag/v5.1.0","date":"2025-03-31T14:04:44Z","type":"stable","version":"v5.1.0"},{"url":"https://github.com/expressjs/express/releases/tag/4.21.2","date":"2024-12-05T22:41:41Z","type":"stable","version":"4.21.2"},{"url":"https://github.com/expressjs/express/releases/tag/4.21.1","date":"2024-10-08T18:38:48Z","type":"stable","version":"4.21.1"},{"url":"https://github.com/expressjs/express/releases/tag/4.21.0","date":"2024-09-11T22:34:26Z","type":"stable","version":"4.21.0"},{"url":"https://github.com/expressjs/express/releases/tag/v5.0.0","date":"2024-09-10T04:51:37Z","type":"stable","version":"v5.0.0"},{"url":"https://github.com/expressjs/express/releases/tag/4.20.0","date":"2024-09-10T02:06:04Z","type":"stable","version":"4.20.0"},{"url":"https://github.com/expressjs/express/releases/tag/v5.0.0-beta.3","date":"2024-03-25T14:59:35Z","type":"prerelease","version":"v5.0.0-beta.3"},{"url":"https://github.com/expressjs/express/releases/tag/4.19.2","date":"2024-03-25T14:32:36Z","type":"stable","version":"4.19.2"},{"url":"https://github.com/expressjs/express/releases/tag/5.0.0-beta.2","date":"2024-03-25T14:59:09Z","type":"prerelease","version":"5.0.0-beta.2"},{"url":"https://github.com/expressjs/express/releases/tag/4.19.1","date":"2024-03-25T14:31:15Z","type":"stable","version":"4.19.1"},{"url":"https://github.com/expressjs/express/releases/tag/4.19.0","date":"2024-03-20T16:43:00Z","type":"stable","version":"4.19.0"},{"url":"https://github.com/expressjs/express/releases/tag/4.18.3","date":"2024-02-29T11:44:48Z","type":"stable","version":"4.18.3"},{"url":"https://github.com/expressjs/express/releases/tag/4.18.2","date":"2022-10-08T20:12:36Z","type":"stable","version":"4.18.2"},{"url":"https://github.com/expressjs/express/releases/tag/4.18.1","date":"2022-04-29T19:32:52Z","type":"stable","version":"4.18.1"}]` | `[{"url":"https://github.com/fastapi/fastapi/releases/tag/0.142.2","date":"2026-09-30T09:50:53Z","type":"stable","version":"0.142.2"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.142.1","date":"2026-09-29T22:36:03Z","type":"stable","version":"0.142.1"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.142.0","date":"2026-09-29T17:56:21Z","type":"stable","version":"0.142.0"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.141.1","date":"2026-07-29T17:17:26Z","type":"stable","version":"0.141.1"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.141.0","date":"2026-07-29T14:47:36Z","type":"stable","version":"0.141.0"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.13","date":"2026-07-28T15:36:47Z","type":"stable","version":"0.140.13"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.12","date":"2026-07-28T15:04:48Z","type":"stable","version":"0.140.12"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.11","date":"2026-07-28T14:33:49Z","type":"stable","version":"0.140.11"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.10","date":"2026-07-28T14:21:00Z","type":"stable","version":"0.140.10"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.9","date":"2026-07-28T12:38:03Z","type":"stable","version":"0.140.9"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.8","date":"2026-07-28T10:31:04Z","type":"stable","version":"0.140.8"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.7","date":"2026-07-27T17:33:02Z","type":"stable","version":"0.140.7"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.6","date":"2026-07-27T16:31:22Z","type":"stable","version":"0.140.6"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.5","date":"2026-07-27T16:02:33Z","type":"stable","version":"0.140.5"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.4","date":"2026-07-27T15:46:29Z","type":"stable","version":"0.140.4"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.3","date":"2026-07-27T15:29:52Z","type":"stable","version":"0.140.3"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.2","date":"2026-07-27T14:14:50Z","type":"stable","version":"0.140.2"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.1","date":"2026-07-27T12:07:15Z","type":"stable","version":"0.140.1"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.140.0","date":"2026-07-24T21:16:20Z","type":"stable","version":"0.140.0"},{"url":"https://github.com/fastapi/fastapi/releases/tag/0.139.2","date":"2026-07-16T15:05:47Z","type":"stable","version":"0.139.2"}]` |
| reliability.status_page | - | yes |
| security.disclosure_policy | yes | - |
| security.scorecard | 8.9 | - |
| security.trust_center | https://expressjs.com/en/advanced/security-updates | https://fastapi.tiangolo.com/tutorial/security/get-current-user/ |
| security.vulnerabilities | `{"count":6,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=npm&package_name=express&per_page=100","last_12m":1,"max_severity":"MODERATE"}` | `{"count":2,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=pypi&package_name=fastapi&per_page=100","last_12m":0,"max_severity":"HIGH"}` |

## Capabilities (Web Frameworks)

| Capability | Express | FastAPI |
|---|:--:|:--:|
| **Core** |  |  |
| Rendering model | - | - |
| File-based routing | ✗ | - |
| Language | JavaScript | Python |
| **Rendering** |  |  |
| Server components | ✗ | - |
| Streaming SSR | ✗ | - |
| **Fullstack** |  |  |
| Built-in API / backend routes | ✓ | ✓ |
| **DX** |  |  |
| First-class TypeScript | ✗ | - |
| Fast refresh / HMR | ✗ | ✓ |
| **Deployment** |  |  |
| Edge runtime support | ✗ | - |

*Source: vioscaleAI. Generated 2026-10-16T16:53:18.782Z. "-" = undocumented, not absent.*