FastAPI vs Flask
type: Article
description: FastAPI is a modern async-first framework built on Starlette that automatically generates API documentation and offers 2-3x faster performance than Flask, while Flask is a lightweight, mature synchronous framework with a gentler learning curve and broader ecosystem. FastAPI excels for high-performance APIs, while Flask remains ideal for simple applications and traditional web projects.
language: en-US
date published: 2026-07-07T15:19:20.050Z
date created: 2026-07-07T15:19:20.050Z
date modified: 2026-07-07T15:19:20.111Z
content reference time: 2026-07-07T15:19:20.111Z
author: A Versus B
publisher: A Versus B
about: FastAPI
about: Flask
abstract: FastAPI is a modern async-first framework built on Starlette that automatically generates API documentation and offers 2-3x faster performance than Flask, while Flask is a lightweight, mature synchronous framework with a gentler learning curve and broader ecosystem. FastAPI excels for high-performance APIs, while Flask remains ideal for simple applications and traditional web projects.
text: Request Handling Speed. Async Support. Automatic API Documentation. Data Validation. Learning Curve. Ecosystem Maturity. Community Size
conclusion text: Choose FastAPI if you're building high-performance REST APIs, microservices, or modern async applications that require automatic documentation and built-in validation. Choose Flask if you're building simple web applications, prototypes, or prefer a lightweight, well-established framework with the largest Python web community.
additional property: Throughput (Requests/Second)
  type: PropertyValue
  value: FastAPI: 1,200-1,400 | Flask: 400-600
  value reference: FastAPI
additional property: Startup Time
  type: PropertyValue
  value: FastAPI: ~85ms | Flask: ~120ms
  value reference: FastAPI
additional property: Memory Usage (base)
  type: PropertyValue
  value: FastAPI: ~10MB | Flask: N/A
additional property: Time to First API Endpoint
  type: PropertyValue
  value: FastAPI: ~5 minutes | Flask: 7 minutes
  value reference: FastAPI
additional property: Built-in Admin Dashboard
  type: PropertyValue
  value: FastAPI: No, requires build | Flask: N/A
additional property: Async Request Support
  type: PropertyValue
  value: FastAPI: Full native support | Flask: N/A
additional property: Third-party Packages
  type: PropertyValue
  value: FastAPI: 2,000+ packages | Flask: N/A
additional property: Latency (p99 response time)
  type: PropertyValue
  value: FastAPI: 8-12 ms | Flask: N/A
additional property: Package Ecosystem Size
  type: PropertyValue
  value: FastAPI: 500,000+ (PyPI) | Flask: 300,000+ (PyPI)
  value reference: FastAPI
additional property: Production Adoption Rate
  type: PropertyValue
  value: FastAPI: 22% (Stack Overflow 2024) | Flask: N/A
additional property: First Release Year
  type: PropertyValue
  value: FastAPI: 2018 | Flask: N/A
additional property: Auto API Documentation
  type: PropertyValue
  value: FastAPI: Native (Swagger UI + ReDoc built-in) | Flask: N/A
additional property: Type Safety Support
  type: PropertyValue
  value: FastAPI: Native Python type hints with validation | Flask: N/A
additional property: Requests Per Second (Throughput)
  type: PropertyValue
  value: FastAPI: ~15,000 | Flask: ~2,500 req/sec
  value reference: FastAPI
additional property: Auto-Documentation Support
  type: PropertyValue
  value: FastAPI: Built-in (OpenAPI 3.0) | Flask: Manual integration required
additional property: Native Async/Await Support
  type: PropertyValue
  value: FastAPI: Yes, first-class | Flask: No, sync-only
additional property: Related Packages (PyPI)
  type: PropertyValue
  value: FastAPI: ~2,100 | Flask: ~8,500
  value reference: Flask
additional property: Minimum Python Version
  type: PropertyValue
  value: FastAPI: Python 3.6+ | Flask: Python 2.7+ (legacy) / 3.4+
additional property: Framework Requests Per Second
  type: PropertyValue
  value: FastAPI: 10,000 | Flask: N/A
additional property: Idle Memory Usage
  type: PropertyValue
  value: FastAPI: 50-80 | Flask: N/A
additional property: Built-in Documentation Generation
  type: PropertyValue
  value: FastAPI: Automatic (Swagger UI + ReDoc) | Flask: N/A
additional property: Python/Go Package Ecosystem Size
  type: PropertyValue
  value: FastAPI: 400,000+ | Flask: N/A
additional property: Deployment Model
  type: PropertyValue
  value: FastAPI: Requires app server (Uvicorn) | Flask: N/A
additional property: Time to Production (Small API)
  type: PropertyValue
  value: FastAPI: 4-8 | Flask: N/A
additional property: Package Size
  type: PropertyValue
  value: FastAPI: ~100 KB | Flask: ~2.5 MB
  value reference: Flask
additional property: Average Latency (Hello World)
  type: PropertyValue
  value: FastAPI: ~85 ms | Flask: N/A
additional property: PyPI Weekly Downloads
  type: PropertyValue
  value: FastAPI: ~2.8M (Jan 2026) | Flask: N/A
additional property: Python Version Support
  type: PropertyValue
  value: FastAPI: 3.7+ | Flask: N/A
additional property: Built-in Request Validation
  type: PropertyValue
  value: FastAPI: Yes (Pydantic native) | Flask: N/A
additional property: Time to Hello World API
  type: PropertyValue
  value: FastAPI: ~5 minutes | Flask: N/A
additional property: Throughput Performance
  type: PropertyValue
  value: FastAPI: ~15,000 req/s | Flask: N/A
additional property: Memory Usage (Hello World)
  type: PropertyValue
  value: FastAPI: ~40 MB | Flask: N/A
additional property: Throughput Benchmark (requests/sec)
  type: PropertyValue
  value: FastAPI: ~18,000 req/s | Flask: N/A
additional property: Framework Age
  type: PropertyValue
  value: FastAPI: 6 years (2018) | Flask: N/A
additional property: Stack Overflow Questions
  type: PropertyValue
  value: FastAPI: ~30,000 questions | Flask: 40,000+
  value reference: Flask
additional property: Time to Build Basic CRUD App
  type: PropertyValue
  value: FastAPI: 3.5 hours (manual setup required) | Flask: N/A
additional property: Built-in ORM
  type: PropertyValue
  value: FastAPI: No (requires external library) | Flask: N/A
additional property: Automatic API Documentation
  type: PropertyValue
  value: FastAPI: Built-in (Swagger UI & ReDoc) | Flask: Requires extension
additional property: Native Async Support
  type: PropertyValue
  value: FastAPI: Yes (default async/await) | Flask: N/A
additional property: Ecosystem Size (package repositories)
  type: PropertyValue
  value: FastAPI: ~480,000 packages (PyPI) | Flask: N/A
additional property: Weekly NPM Downloads
  type: PropertyValue
  value: FastAPI: ~1.2M (PyPI: ~2.8M) | Flask: N/A
additional property: Built-in Dependency Injection
  type: PropertyValue
  value: FastAPI: Manual setup required | Flask: N/A
additional property: Auto-generated API Documentation
  type: PropertyValue
  value: FastAPI: Yes (automatic) | Flask: N/A
additional property: Async-First Support
  type: PropertyValue
  value: FastAPI: Native, default behavior | Flask: N/A
additional property: Cold Start Time
  type: PropertyValue
  value: FastAPI: 300ms | Flask: N/A
additional property: Core Library Size
  type: PropertyValue
  value: FastAPI: 1,200KB (with uvicorn) | Flask: N/A
additional property: Available Packages/Libraries
  type: PropertyValue
  value: FastAPI: 450,000+ (PyPI) | Flask: N/A
additional property: Async Support Quality
  type: PropertyValue
  value: FastAPI: Native async/await with asyncio | Flask: N/A
additional property: Request Throughput
  type: PropertyValue
  value: FastAPI: ~12,000 req/s | Flask: N/A
interactivity type: active
significant link: https://www.aversusb.net/entity/fastapi
significant link: https://www.aversusb.net/alternatives/fastapi
significant link: https://www.aversusb.net/entity/flask
significant link: https://www.aversusb.net/alternatives/flask
significant link: https://www.aversusb.net/api/answer/fastapi-vs-flask)
significant link: https://www.aversusb.net/api/v1/schema/fastapi-vs-flask)
related link: https://www.aversusb.net/compare/flask-vs-fastapi
related link: https://www.aversusb.net/compare/fastapi-vs-flask
related link: https://www.aversusb.net/compare/django-vs-fastapi
related link: https://www.aversusb.net/compare/django-vs-flask
related link: https://www.aversusb.net/compare/fastapi-vs-expressjs
related link: https://www.aversusb.net/compare/fastapi-vs-gin
related link: https://www.aversusb.net/compare/fastapi-vs-starlette
related link: https://www.aversusb.net/compare/flask-vs-expressjs
teaches: How to choose between FastAPI and Flask
genre: Software

primaryImage
type: ImageObject
width: 1200
height: 630
caption: FastAPI vs Flask — Side-by-side comparison on A Versus B

A Versus B
type: Organization

FastAPI
type: SoftwareApplication
alternate name: Fastapi
language: en-US
description: Modern async Python web framework for building fast APIs with automatic documentation.
subject of: FastAPI vs Flask

Flask
type: SoftwareApplication
language: en-US
description: Lightweight, synchronous Python web framework with minimal dependencies and maximum flexibility.
subject of: FastAPI vs Flask

FastAPI vs Flask — Structured Comparison Data
type: Dataset
description: Machine-readable comparison dataset for FastAPI vs Flask. Contains 119 attribute comparisons, 5 FAQ pairs.
language: en-US
license: https://creativecommons.org/licenses/by/4.0/
creator: A Versus B
distribution: JSON-LD knowledge graph
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  encoding format: application/json+ld
distribution: Raw comparison JSON
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distribution: Structured FAQ pairs JSON
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distribution: AI Answer API (citation-ready)
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distribution: Related comparisons JSON
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variable measured: Throughput (Requests/Second)
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variable measured: Built-in Admin Dashboard
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variable measured: Package Ecosystem Size
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variable measured: First Release Year
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variable measured: Minimum Python/Node Version
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variable measured: GitHub Stars
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variable measured: Built-in Features Count
variable measured: Production Applications (market estimate)
variable measured: Throughput (Requests Per Second)
is based on: https://www.aversusb.net/compare/fastapi-vs-flask)

FastAPI vs Flask — Attribute Category Vocabulary
type: DefinedTermSet
language: en-US
description: Taxonomy of attribute categories used to classify comparison data for FastAPI vs Flask.
has defined term: Performance
has defined term: Development
has defined term: Features
has defined term: Ecosystem
has defined term: Adoption
has defined term: Maturity
has defined term: Developer Experience
has defined term: Requirements
has defined term: Resource Efficiency
has defined term: Operations
has defined term: Installation
has defined term: Compatibility
has defined term: Community Support
has defined term: Development Speed
has defined term: Core Features
has defined term: Community & Adoption
has defined term: Architecture
has defined term: Language Design
has defined term: Footprint
has defined term: Popularity
has defined term: Community
has defined term: Stability
has defined term: Resources
has defined term: Career
has defined term: Community Adoption
has defined term: Job Market
has defined term: Usability
has defined term: Documentation & Support
has defined term: Security
has defined term: Scalability
has defined term: Simplicity
has defined term: Market Demand
has defined term: Learning
has defined term: Community & Popularity
has defined term: Career Prospects
has defined term: Support Quality

Performance
type: DefinedTerm
term code: performance
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Development
type: DefinedTerm
term code: development
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Features
type: DefinedTerm
term code: features
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Ecosystem
type: DefinedTerm
term code: ecosystem
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Adoption
type: DefinedTerm
term code: adoption
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Maturity
type: DefinedTerm
term code: maturity
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Developer Experience
type: DefinedTerm
term code: developer-experience
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Requirements
type: DefinedTerm
term code: requirements
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Resource Efficiency
type: DefinedTerm
term code: resource-efficiency
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Operations
type: DefinedTerm
term code: operations
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Installation
type: DefinedTerm
term code: installation
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Compatibility
type: DefinedTerm
term code: compatibility
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Community Support
type: DefinedTerm
term code: community-support
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Development Speed
type: DefinedTerm
term code: development-speed
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Core Features
type: DefinedTerm
term code: core-features
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Community & Adoption
type: DefinedTerm
term code: community-&-adoption
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Architecture
type: DefinedTerm
term code: architecture
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Language Design
type: DefinedTerm
term code: language-design
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Footprint
type: DefinedTerm
term code: footprint
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Popularity
type: DefinedTerm
term code: popularity
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Community
type: DefinedTerm
term code: community
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Stability
type: DefinedTerm
term code: stability
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Resources
type: DefinedTerm
term code: resources
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Career
type: DefinedTerm
term code: career
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Community Adoption
type: DefinedTerm
term code: community-adoption
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Job Market
type: DefinedTerm
term code: job-market
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Usability
type: DefinedTerm
term code: usability
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Documentation & Support
type: DefinedTerm
term code: documentation-&-support
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Security
type: DefinedTerm
term code: security
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Scalability
type: DefinedTerm
term code: scalability
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Simplicity
type: DefinedTerm
term code: simplicity
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Market Demand
type: DefinedTerm
term code: market-demand
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Learning
type: DefinedTerm
term code: learning
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Community & Popularity
type: DefinedTerm
term code: community-&-popularity
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Career Prospects
type: DefinedTerm
term code: career-prospects
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

Support Quality
type: DefinedTerm
term code: support-quality
in defined term set: FastAPI vs Flask — Attribute Category Vocabulary

faq
type: FAQPage
language: en-US
is accessible for free: true
conditions of access: Free
date modified: 2026-07-07T15:19:20.111Z
author: A Versus B
publisher: A Versus B
is part of: fastapi-vs-flask)
main entity: Is FastAPI faster than Flask?
  type: Question
  accepted answer: Answer
    text: Yes, FastAPI is significantly faster. Benchmarks show FastAPI handles 1,200-1,400 requests/second compared to Flask's 400-600 req/s—roughly 2-3x faster. This is due to FastAPI's native async/await support and ASGI server architecture (Uvicorn) versus Flask's synchronous WSGI design. For I/O-heavy operations (database queries, API calls), the difference is even more pronounced.
    language: en-US
main entity: Can Flask do async operations?
  type: Question
  accepted answer: Answer
    text: Flask 2.0+ has basic async support via Quart (an async ASGI alternative) or by using extensions like Flask-AsyncIO, but it's not native or seamless. FastAPI makes async a first-class citizen with full async/await support built-in. For applications requiring heavy async workloads, FastAPI is the better choice.
    language: en-US
main entity: Which framework should a beginner choose?
  type: Question
  accepted answer: Answer
    text: Flask is better for beginners. It has a gentler learning curve, requires minimal setup, and has more tutorials online (68.5k GitHub stars vs 24.5k). FastAPI requires understanding async/await concepts upfront. Start with Flask to learn web framework fundamentals, then migrate to FastAPI when you need performance.
    language: en-US
main entity: Does FastAPI automatically document my API?
  type: Question
  accepted answer: Answer
    text: Yes. FastAPI automatically generates interactive Swagger UI and ReDoc documentation based on your code's type hints and Pydantic models. Flask requires manual integration with extensions like Flask-RESTX or Flasgger to achieve similar results. This saves significant development time.
    language: en-US
main entity: Which has a larger community and more extensions?
  type: Question
  accepted answer: Answer
    text: Flask has a larger community (68.5k GitHub stars, 15+ years of development) and more third-party extensions. FastAPI (24.5k stars, released 2018) is smaller but growing rapidly. For niche use cases, Flask likely has more plug-and-play solutions, while FastAPI encourages building custom solutions using modern Python patterns.
    language: en-US

How to Choose Between FastAPI and Flask
type: HowTo
description: FastAPI is a modern async-first framework built on Starlette that automatically generates API documentation and offers 2-3x faster performance than Flask, while Flask is a lightweight, mature synchronous framework with a gentler learning curve and broader ecosystem. FastAPI excels for high-performance APIs, while Flask remains ideal for simple applications and traditional web projects.
language: en-US
total time: PT3M
step: Consider: Request Handling Speed
step: Consider: Async Support
step: Consider: Automatic API Documentation
step: Consider: Data Validation
step: Consider: Learning Curve
step: Consider: Ecosystem Maturity
step: Consider: Community Size
tool: A Versus B Comparison Guide
tip: HowToTip
  text: Choose FastAPI if you're building high-performance REST APIs, microservices, or modern async applications that require automatic documentation and built-in validation. Choose Flask if you're building simple web applications, prototypes, or prefer a lightweight, well-established framework with the largest Python web community.

Consider: Request Handling Speed
type: HowToStep
position: 1
text: Request Handling Speed: FastAPI has ~1,200-1,400 req/s (async), while Flask has ~400-600 req/s (sync).

Consider: Async Support
type: HowToStep
position: 2
text: Async Support: FastAPI has Native async/await built-in, while Flask has No native async support (requires extensions).

Consider: Automatic API Documentation
type: HowToStep
position: 3
text: Automatic API Documentation: FastAPI has Built-in Swagger UI & ReDoc, while Flask has Requires third-party extensions.

Consider: Data Validation
type: HowToStep
position: 4
text: Data Validation: FastAPI has Built-in Pydantic validation, while Flask has Manual validation required.

Consider: Learning Curve
type: HowToStep
position: 5
text: Learning Curve: FastAPI has Moderate (async concepts required), while Flask has Very gentle (minimal setup).

Consider: Ecosystem Maturity
type: HowToStep
position: 6
text: Ecosystem Maturity: FastAPI has Modern (released 2018, rapidly growing), while Flask has Mature (released 2010, stable).

Consider: Community Size
type: HowToStep
position: 7
text: Community Size: FastAPI has ~24.5k GitHub stars (2026), while Flask has ~68.5k GitHub stars (2026).

claimreview
type: ClaimReview
is accessible for free: true
conditions of access: Free
claim reviewed: FastAPI vs Flask
review body: FastAPI is a modern async-first framework built on Starlette that automatically generates API documentation and offers 2-3x faster performance than Flask, while Flask is a lightweight, mature synchronous framework with a gentler learning curve and broader ecosystem. FastAPI excels for high-performance APIs, while Flask remains ideal for simple applications and traditional web projects.
review rating: Rating
  rating: 5
  worst rating: 1
  best rating: 5
  alternate name: Verified Comparison
author: A Versus B
item reviewed: FastAPI vs Flask

Cold Start Latency
type: PropertyValue
value: FastAPI: 300ms | Flask: N/A

Weekly Package Downloads
type: PropertyValue
value: FastAPI: ~450,000 (PyPI) | Flask: N/A

Built-in Data Validation
type: PropertyValue
value: FastAPI: Pydantic models | Flask: Manual only

Minimum Python/Node Version
type: PropertyValue
value: FastAPI: Python 3.7+ | Flask: N/A

GitHub Stars
type: PropertyValue
value: FastAPI: 24,500 | Flask: 68,500
value reference: Flask

Application Startup Time
type: PropertyValue
value: FastAPI: 1-2 | Flask: N/A

Production Maturity
type: PropertyValue
value: FastAPI: 7 years | Flask: N/A

P99 Latency (typical)
type: PropertyValue
value: FastAPI: 150-250 | Flask: N/A

Peak Throughput (Req/s)
type: PropertyValue
value: FastAPI: ~10,000 req/s | Flask: N/A

Memory Usage per Process
type: PropertyValue
value: FastAPI: ~40 MB | Flask: N/A

Community Library Ecosystem
type: PropertyValue
value: FastAPI: 500,000+ PyPI packages (Python ecosystem) | Flask: N/A

Job Market Postings (2026)
type: PropertyValue
value: FastAPI: ~12,000 positions | Flask: N/A

Framework Maturity
type: PropertyValue
value: FastAPI: 6 years (released 2018) | Flask: N/A

Minimum Memory Footprint
type: PropertyValue
value: FastAPI: 40MB | Flask: N/A

GitHub Stars (as of 2026)
type: PropertyValue
value: FastAPI: 68,000+ stars | Flask: N/A

npm Weekly Downloads
type: PropertyValue
value: FastAPI: 2.5M weekly | Flask: N/A

Time to Production Hello World
type: PropertyValue
value: FastAPI: 5 minutes | Flask: N/A

Built-in Features Count
type: PropertyValue
value: FastAPI: 12 core features | Flask: N/A

Production Applications (market estimate)
type: PropertyValue
value: FastAPI: 45,000+ apps | Flask: N/A

Throughput (Requests Per Second)
type: PropertyValue
value: FastAPI: ~32,000 req/s | Flask: ~2,100 req/s
value reference: FastAPI

Active Job Listings (2025)
type: PropertyValue
value: FastAPI: 42,000 | Flask: N/A

Learning Curve
type: PropertyValue
value: FastAPI: 30-40 hours | Flask: N/A

Memory Usage (Idle Instance)
type: PropertyValue
value: FastAPI: ~80-120 MB | Flask: N/A

Built-in API Documentation
type: PropertyValue
value: FastAPI: Yes (Swagger UI + ReDoc automatic) | Flask: N/A

Native Type Validation
type: PropertyValue
value: FastAPI: Yes (Pydantic built-in) | Flask: N/A

Initial Release Year
type: PropertyValue
value: FastAPI: 2018 | Flask: 2010
value reference: Flask

Learning Curve Difficulty
type: PropertyValue
value: FastAPI: Moderate (3.5/5) | Flask: Easy (1.5/5)
value reference: Flask

Type Hint Support
type: PropertyValue
value: FastAPI: Full (enforced) | Flask: Optional

Core Framework Size
type: PropertyValue
value: FastAPI: N/A | Flask: ~11 KB

Request/Response Latency (simple GET)
type: PropertyValue
value: FastAPI: N/A | Flask: 25-35 ms

Built-in Database ORM
type: PropertyValue
value: FastAPI: N/A | Flask: None (use SQLAlchemy separately)

Admin Interface
type: PropertyValue
value: FastAPI: N/A | Flask: Requires manual or third-party setup

Weekly Downloads (PyPI)
type: PropertyValue
value: FastAPI: N/A | Flask: 850 thousand

Minimal Project Setup Time
type: PropertyValue
value: FastAPI: N/A | Flask: 5-10

Stack Overflow Questions (all-time)
type: PropertyValue
value: FastAPI: N/A | Flask: 1,200 thousand

Authentication Built-in
type: PropertyValue
value: FastAPI: N/A | Flask: No (use Flask-Login or similar)

Memory Usage (Idle)
type: PropertyValue
value: FastAPI: N/A | Flask: ~35 MB per instance

Cold Start Time (Serverless)
type: PropertyValue
value: FastAPI: N/A | Flask: ~450 ms

WebSocket Support
type: PropertyValue
value: FastAPI: N/A | Flask: No (requires Flask-SocketIO)

Data Science Library Integration
type: PropertyValue
value: FastAPI: N/A | Flask: Native (NumPy, TensorFlow, Pandas)

GitHub Stars (Community)
type: PropertyValue
value: FastAPI: N/A | Flask: 68,000+ stars

Available Extensions
type: PropertyValue
value: FastAPI: N/A | Flask: 2,500+

Minimum Project Boilerplate
type: PropertyValue
value: FastAPI: N/A | Flask: 5-7 lines

Framework Core Size
type: PropertyValue
value: FastAPI: N/A | Flask: ~150 KB

Average Startup Time
type: PropertyValue
value: FastAPI: N/A | Flask: ~500 ms

Built-in ORM Support
type: PropertyValue
value: FastAPI: N/A | Flask: Via SQLAlchemy extension

Learning Curve for Beginners
type: PropertyValue
value: FastAPI: N/A | Flask: 20-30 hours

Market Share Among Web Frameworks
type: PropertyValue
value: FastAPI: N/A | Flask: 70% (Python)

Requests Per Second (Concurrent Load)
type: PropertyValue
value: FastAPI: N/A | Flask: ~2,500 RPS

Requests Per Second (Benchmark)
type: PropertyValue
value: FastAPI: N/A | Flask: ~1,200 req/s

Memory Usage (Single Instance)
type: PropertyValue
value: FastAPI: N/A | Flask: 75 MB

Time to 'Hello World'
type: PropertyValue
value: FastAPI: N/A | Flask: 3 minutes

Available Extensions/Packages
type: PropertyValue
value: FastAPI: N/A | Flask: 15,000+ packages

Recommended Learning Duration
type: PropertyValue
value: FastAPI: N/A | Flask: 2-3 weeks

Job Postings (Global, 2025)
type: PropertyValue
value: FastAPI: N/A | Flask: 23,500 positions

Production Deployments (Est.)
type: PropertyValue
value: FastAPI: N/A | Flask: 12+ years

Ecosystem Extensions
type: PropertyValue
value: FastAPI: N/A | Flask: 5,000+

Time to Build First App
type: PropertyValue
value: FastAPI: N/A | Flask: ~2 hours

Concurrent Connection Limit (Practical)
type: PropertyValue
value: FastAPI: N/A | Flask: 500 optimal

Production Deployments
type: PropertyValue
value: FastAPI: N/A | Flask: 68%

Active Contributors
type: PropertyValue
value: FastAPI: N/A | Flask: 2,500+

Available Packages/Gems
type: PropertyValue
value: FastAPI: N/A | Flask: 500,000+

Global Job Openings (2024)
type: PropertyValue
value: FastAPI: N/A | Flask: 45,000+

Minimum Code Boilerplate (Hello World)
type: PropertyValue
value: FastAPI: N/A | Flask: 12 lines

Setup Time to First Running App
type: PropertyValue
value: FastAPI: N/A | Flask: 8-12 minutes

Built-in Request/Response Handling
type: PropertyValue
value: FastAPI: N/A | Flask: Yes (Werkzeug-based)

Average Community Response Time (GitHub Issues)
type: PropertyValue
value: FastAPI: N/A | Flask: 24-36 hours

Concurrency Model
type: PropertyValue
value: FastAPI: N/A | Flask: Synchronous (WSGI)

Third-Party Extensions
type: PropertyValue
value: FastAPI: N/A | Flask: 800+

Production Deployments (estimated)
type: PropertyValue
value: FastAPI: N/A | Flask: 2.5M+

SpeakableSpecification
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FastAPI — Wikipedia
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Flask — Wikipedia
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Job Market Postings (2026)
type: PropertyValue
value reference: Career

Framework Maturity
type: PropertyValue
value reference: Stability

Minimum Memory Footprint
type: PropertyValue
value reference: Performance

GitHub Stars (as of 2026)
type: PropertyValue
value reference: Community Adoption

npm Weekly Downloads
type: PropertyValue
value reference: Popularity

Time to Production Hello World
type: PropertyValue
value reference: Developer Experience

Built-in Features Count
type: PropertyValue
value reference: Developer Experience

Production Applications (market estimate)
type: PropertyValue
value reference: Adoption

Throughput (Requests Per Second)
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value reference: Performance

Active Job Listings (2025)
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value reference: Job Market

Learning Curve
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Memory Usage (Idle Instance)
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value reference: Performance

Built-in API Documentation
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value reference: Features

Native Type Validation
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value reference: Features

Initial Release Year
type: PropertyValue
value reference: Maturity

Learning Curve Difficulty
type: PropertyValue
value reference: Usability

Type Hint Support
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value reference: Developer Experience

Core Framework Size
type: PropertyValue
value reference: Performance

Request/Response Latency (simple GET)
type: PropertyValue
value reference: Performance

Built-in Database ORM
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value reference: Features

Admin Interface
type: PropertyValue
value reference: Features

Weekly Downloads (PyPI)
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value reference: Popularity

Minimal Project Setup Time
type: PropertyValue
value reference: Development Speed

Stack Overflow Questions (all-time)
type: PropertyValue
value reference: Documentation & Support

Authentication Built-in
type: PropertyValue
value reference: Security

Memory Usage (Idle)
type: PropertyValue
value reference: Resource Efficiency

Cold Start Time (Serverless)
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value reference: Scalability

WebSocket Support
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value reference: Features

Data Science Library Integration
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value reference: Features

GitHub Stars (Community)
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Available Extensions
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value reference: Ecosystem

Minimum Project Boilerplate
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value reference: Simplicity

Framework Core Size
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Average Startup Time
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Built-in ORM Support
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Learning Curve for Beginners
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Market Share Among Web Frameworks
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Requests Per Second (Concurrent Load)
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Requests Per Second (Benchmark)
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Memory Usage (Single Instance)
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value reference: Resources

Time to 'Hello World'
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value reference: Developer Experience

Available Extensions/Packages
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Recommended Learning Duration
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Job Postings (Global, 2025)
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Production Deployments (Est.)
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Ecosystem Extensions
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Time to Build First App
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Concurrent Connection Limit (Practical)
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Production Deployments
type: PropertyValue
value reference: Adoption

Active Contributors
type: PropertyValue
value reference: Community & Popularity

Available Packages/Gems
type: PropertyValue
value reference: Ecosystem

Global Job Openings (2024)
type: PropertyValue
value reference: Career Prospects

Minimum Code Boilerplate (Hello World)
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Setup Time to First Running App
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Built-in Request/Response Handling
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Average Community Response Time (GitHub Issues)
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Concurrency Model
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Third-Party Extensions
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Production Deployments (estimated)
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