FastAPI VS Requestly

Compare FastAPI VS Requestly and see what are their differences

BusinessXray

Automated 60-second forensic business auditing pipeline powered by OpenAI Nano AI. Built for consultants and analysts. featured

Contents:

» Base Details
» Videos
» Reviews
» Alternatives

FastAPI

FastAPI is an Open Source, modern, fast (high-performance), web framework for building APIs with Python 3.6+ based on standard Python type hints.

Requestly

A Powerful API Mocking and Testing Tool

Landing page //
2023-05-14

Requestly //
2025-02-12
Rest Client //
2025-02-12
HTTP Interceptor //
2025-02-12
API Mocking //
2025-02-12
Requestly //
2025-02-12

Requestly is a modern and powerful companion for API Development and Testing. It is an open-source tool purpose-built to speed up and simplify API development workflow for developers and QAs. It is a combination of API Client and HTTP Interceptor that helps create and share API Contracts, testing APIs, and easily mock and integrate them into web and mobile apps.

FastAPI

Website: fastapi.tiangolo.com
Pricing URL: -
$ Details: free
Platforms: -
Release Date: -
Startup details
Country: Colombia

Edit details

Requestly

Website: requestly.com
Pricing URL: Official Requestly Pricing
$ Details: freemium
Platforms: Google Chrome Firefox Edge Safari Brave Opera Vivaldi Android Windows Linux Mac OSX MacOS
Release Date: 2021 January
Startup details
Country: United States
State: California
City: San Francisco
Founder(s): Sachin Jain, Sagar Soni, Sahil Gupta
Employees: 20 - 49

Edit details

FastAPI features and specs

High Performance
Built on Starlette and Pydantic, FastAPI is one of the fastest frameworks for Python, providing high performance due to its asynchronous request handling.
Automatic Interactive API Documentation
FastAPI automatically generates interactive API documentation via Swagger UI and ReDoc, which are very helpful for development and testing.
Type Checking and Validation
With Pydantic models and Python type hints, FastAPI provides automatic data validation and type checking, reducing the chance of runtime errors.
Ease of Use
Its syntax and design make it easy to learn for Python developers, offering a smooth development experience while reducing boilerplate code.
Asynchronous Support
FastAPI supports asynchronous programming, allowing for better performance for I/O-bound operations, making it optimal for handling many simultaneous connections.
Extensive Documentation
It has comprehensive and well-structured documentation, which is very useful for both beginners and advanced users.
Community and Ecosystem
FastAPI has a growing community and ecosystem, with many plugins and integrations available to extend its functionality.

Possible disadvantages of FastAPI

Learning Curve for Asynchronous Programming
Although FastAPI itself is easy to learn, grasping the concepts of asynchronous programming in Python can be challenging for beginners.
Complex Dependencies
Using Pydantic for advanced validation can make the request models complex, requiring a deeper understanding of Pydantic and its functionalities.
Early Stage Libraries
Some third-party libraries and extensions specifically tailored for FastAPI might still be in early stages of development and lack long-term stability.
Limited Real-World Examples
Although the documentation is extensive, there might be limited real-world examples and case studies readily available compared to more mature frameworks.
Deployment Complexity
Deploying FastAPI applications might be more complex in comparison to traditional synchronous frameworks, mainly due to the need for asynchronous server setups.

Requestly features and specs

Redirect URL
Block Network Requests
Modify Request & Response Header
Modify Response
Supercharge Selenium
Session Replay
Modify Query Params
Team Workspace
API Client
API Mocks
GraphQL Support
Zero Setup
Auto Capture Sessions
Network Logs
Console Logs

Analysis of FastAPI

Overall verdict

FastAPI is widely regarded as a good choice, especially for applications that require high performance, scalability, and modern Python features. It is suitable for both simple and complex projects, making it a versatile tool in the web development ecosystem.

Why this product is good

FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.7+ based on standard Python type hints. It is built on top of Starlette for web framework capabilities and Pydantic for data validation and settings management. FastAPI is known for its excellent performance, automatic generation of interactive API documentation (with Swagger and Redoc), and support for asynchronous programming. Developers appreciate its ease of use, detailed documentation, and helpful error messages.

Recommended for

Developers building RESTful APIs
Teams looking for a high-performance ASGI-based web framework
Projects that require asynchronous programming capabilities
Applications needing automatic generation of interactive API documentation
Python developers who prefer utilizing type hints for code clarity and validation

Analysis of Requestly

Overall verdict

Requestly is generally regarded as a good tool due to its comprehensive functionalities and ease of use. Its ability to seamlessly manage network requests makes it suitable for both beginners and experienced developers.

Why this product is good

Requestly is widely considered a valuable tool because it offers robust and flexible features for intercepting and modifying network requests. Developers and QA testers appreciate it for its ability to simulate and debug API calls efficiently. It is particularly useful for testing changes without altering the codebase and for working with web applications in development and production environments.

Recommended for

Developers looking to debug and test API endpoints.
Quality Assurance (QA) teams that require reliable testing tools for web applications.
Technical professionals who manage network traffic and need to modify or redirect requests effortlessly.
Anyone involved in web development who needs to simulate network conditions or test application behavior under different scenarios.

FastAPI videos

+ Add

FastAPI from the ground up

Requestly videos

+ Add

Get Started with Requestly

Category Popularity

0-100% (relative to FastAPI and Requestly)

FastAPI

Requestly

Developer Tools

77 77%

Developer Tools

23% 23

API Tools

100 100%

API Tools

0% 0

Testing

0 0%

Testing

100% 100

Web Frameworks

100 100%

Web Frameworks

0% 0

Questions & Answers

As answered by people managing FastAPI and Requestly.

Who are some of the biggest customers of your product?

Requestly's answer:

Verizon
AT&T
Adobe
Salesforce
Telegraph
Intuit
Verizon

How would you describe the primary audience of your product?

Requestly's answer:

Front-end developers, QAs, PMs, Digital Marketers

What makes your product unique?

Requestly's answer:

Requestly is an open-source API development and testing tool that combines the capabilities of an API Client and HTTP Interceptor, making it a better alternative to Postman + Charles Proxy. It simplifies API mocking, request modification, and debugging with an intuitive no-code interface, enabling developers and QAs to test APIs efficiently.

User comments

Share your experience with using FastAPI and Requestly. For example, how are they different and which one is better?

Reviews

These are some of the external sources and on-site user reviews we've used to compare FastAPI and Requestly

FastAPI Reviews

Kurslog team

· Working at Kurslog · 3 months ago

When our backend team needs to build services for data parsing, aggregators, or high-load APIs, FastAPI is our absolute go-to choice. It completely lives up to its name-development speed is outstanding.

The combination of Pydantic for data validation and built-in async support keeps our shared codebase clean, strictly typed, and reliable. But the biggest highlight for our cross-functional team is the automatic generation of interactive OpenAPI (Swagger) documentation. Our frontend and mobile developers no longer have to wait for backend engineers to manually update API docs; everything stays perfectly in sync automatically. It has drastically improved our team's communication and delivery speed.

🏁 Competitors: Django, Flask, ExpressJS, Nest.js, Spring Boot

👍 Pros: Blazing fast performance (on par with nodejs and go)|Native asynchronous support out of the box|Automatic, interactive documentation generation (swagger/redoc)|Strict typing and data validation with pydantic

👎 Cons: Smaller plug-and-play ecosystem compared to older frameworks like django|Requires our architects to design the project structure and directory layout from scratch

The 20 Best Laravel Alternatives for Web Development

FastAPI, as the name hints, is a swift mover. Built on Starlette, it’s all about speed and performance with Python. Crafting API masterpieces at the speed of light, now that’s something.

Source: tms-outsource.com

25 Python Frameworks to Master

Since its release in 2018, it has rapidly gained popularity due to its great performance and simplicity. In fact, according to PyPi Stats, FastAPI has over 9 million monthly downloads, surpassing even full-stack frameworks like Django.

Source: kinsta.com

3 Web Frameworks to Use With Python

myapp/ is the main directory of your FastAPI application. It includes all the other files and directories needed for the application.static/ is a directory used to store static assets such as CSS, JavaScript, and image files. These assets are served directly by the web server and are typically used to add visual styling and interactivity to the application.css/, img/, js/...

Source: www.stratascratch.com

Best Alternatives to FastAPI App Free for Windows (2021)

FastAPI Alternative – So many alternatives app to FastAPI that you must to know out there. And, looking for an ideal software was not easy matter. Lucky you, at this page you can find the best replacement app for FastAPI. So what you are waiting for, get the latest FastAPI alternative app for Windows 10 from this page.

Source: alternativetoapp.com

Top 5 Back-End Frameworks to Consider for Web Development in 2021

FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.6+ based on standard Python type hints. It is fast when compared to other major Python frameworks like Flask and Django. FastAPI gives great flexibility to fulfill businesses’ API needs in today’s evolving world.

Source: www.fissionlabs.com

Requestly Reviews

Comparing Charles Proxy, Fiddler, Wireshark, and Requestly

On the pricing front, Requestly strikes a balance between affordability and functionality. It is an open-source tool, offering freemium to individual developers and affordable pricing plans for team collaboration. We have also clearly differentiated how Requestly differs from Wireshark and other web debugging tools like Proxyman, Modheader, and HTTP ToolKit separately.

Source: dev.to

Social recommendations and mentions

Based on our record, FastAPI should be more popular than Requestly. It has been mentiond 311 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

FastAPI mentions (311)

Shipping Sovereign SDK: Cryptographic Forensic Receipts and the End of the AI "Prose Tax"
The Sovereign SDK is a Python-native framework designed to minimize prose overhead while generating ironclad, cryptographic execution receipts for AI agents, complete with drop-in FastAPI/Starlette ASGI middleware. - Source: dev.to / about 1 month ago
5-Minute AI Jobs and Closed Tabs — Why We Built Replay-Then-Tail SSE
We had a feature in production where a single user request could run for five-plus minutes — fetch documents, chunk them, hit an LLM per chunk, synthesize a final answer. We did the obvious thing first: a FastAPI handler that ran the pipeline and streamed progress back to the browser over Server-Sent Events. - Source: dev.to / 2 months ago
FastAPI With LangChain and MongoDB
FastAPI is a Python framework for building APIs quickly, efficiently, and with very little code. - Source: dev.to / 3 months ago
I Built A " CrowdSense AI " : A Scalable, Context-Aware Platform for Smart Stadiums
Backend: Python-based FastAPI for its asynchronous I/O capabilities and rapid JSON serialization. - Source: dev.to / 3 months ago
Async PyMongo in FastAPI
FastAPI is a high-performance web framework that is production-ready and designed for building APIs in python, with roots embedded in asynchronous programming. It embraces Python’s asyncio model as its core principle rather than treating it as optional. This design choice gives FastAPI leverage for I/O bound workloads such as db access, external API calls and real-time data streaming. - Source: dev.to / 3 months ago

Requestly mentions (35)

Why You Need a Local-First API Client (With Hands-On Example)
If you want to try a local-first workflow, you can start using Requestly here: https://requestly.com. - Source: dev.to / 7 months ago
How to use Cursor to Generate API Testcases in Requestly
That’s where automation changes the game. By pairing Cursor, an AI-powered coding assistant, with Requestly's local-first API testing and mocking platform, you can offload the grunt work of writing tests to AI while keeping execution secure and reproducible on your own system. In this article, we’ll walk through how to set up Cursor with Requestly, generate test cases automatically, and run them end-to-end so that... - Source: dev.to / 7 months ago
These 20 Awesome API Clients Will Change How You Work with APIs
Requestly is a versatile browser extension and web client used to intercept, mock, and debug APIs in real-time—perfect for frontend developers. - Source: dev.to / about 1 year ago
Best Tools for GraphQL Development in 2025
Requestly is a powerful tool for modifying GraphQL responses, intercepting requests, and debugging API interactions. It allows developers to tweak request bodies, capture GraphQL traffic, and share sessions for easier debugging and collaboration. - Source: dev.to / over 1 year ago
How Not to Use AI in Software Development
Learn more at https://requestly.com/. - Source: dev.to / over 1 year ago