Add tool

ExpressJS vs Flask: What are the differences?

What is ExpressJS? Sinatra inspired web development framework for node.js -- insanely fast, flexible, and simple. Express is a minimal and flexible node.js web application framework, providing a robust set of features for building single and multi-page, and hybrid web applications.

What is Flask? a microframework for Python based on Werkzeug, Jinja 2 and good intentions. Flask is intended for getting started very quickly and was developed with best intentions in mind.

ExpressJS and Flask can be categorized as "Microframeworks (Backend)" tools.

"Simple", "Node.js" and "Javascript" are the key factors why developers consider ExpressJS; whereas "Lightweight", "Python" and "Minimal" are the primary reasons why Flask is favored.

ExpressJS and Flask are both open source tools. It seems that Flask with 45.2K GitHub stars and 12.7K forks on GitHub has more adoption than ExpressJS with 44.6K GitHub stars and 7.48K GitHub forks.

Twitter, Intuit, and OpenTable are some of the popular companies that use ExpressJS, whereas Flask is used by Netflix, reddit, and Lyft. ExpressJS has a broader approval, being mentioned in 854 company stacks & 788 developers stacks; compared to Flask, which is listed in 511 company stacks and 531 developer stacks.

What is ExpressJS?

Express is a minimal and flexible node.js web application framework, providing a robust set of features for building single and multi-page, and hybrid web applications.

What is Flask?

Flask is intended for getting started very quickly and was developed with best intentions in mind.

Want advice about which of these to choose?Ask the StackShare community!

Why do developers choose ExpressJS?
Why do developers choose Flask?

Sign up to add, upvote and see more prosMake informed product decisions

What are the cons of using ExpressJS?
What are the cons of using Flask?
What companies use ExpressJS?
What companies use Flask?

Sign up to get full access to all the companiesMake informed product decisions

What tools integrate with ExpressJS?
What tools integrate with Flask?

Sign up to get full access to all the tool integrationsMake informed product decisions

What are some alternatives to ExpressJS and Flask?
Koa aims to be a smaller, more expressive, and more robust foundation for web applications and APIs. Through leveraging generators Koa allows you to ditch callbacks and greatly increase error-handling. Koa does not bundle any middleware.
Lots of people use React as the V in MVC. Since React makes no assumptions about the rest of your technology stack, it's easy to try it out on a small feature in an existing project.
Django is a high-level Python Web framework that encourages rapid development and clean, pragmatic design.
Go is expressive, concise, clean, and efficient. Its concurrency mechanisms make it easy to write programs that get the most out of multicore and networked machines, while its novel type system enables flexible and modular program construction. Go compiles quickly to machine code yet has the convenience of garbage collection and the power of run-time reflection. It's a fast, statically typed, compiled language that feels like a dynamically typed, interpreted language.
nginx [engine x] is an HTTP and reverse proxy server, as well as a mail proxy server, written by Igor Sysoev. According to Netcraft nginx served or proxied 30.46% of the top million busiest sites in Jan 2018.
See all alternatives
Decisions about ExpressJS and Flask
No stack decisions found
Interest over time
Reviews of ExpressJS and Flask
Avatar of mjhea0
Software Engineer at TestDriven Labs
Review ofFlaskFlask

Flask is a light, yet powerful Python web framework perfect for quickly building smaller web applications. It's a "micro-framework" that's easy to learn and simple to use, so it's perfect for those new to web development as well as those looking to rapidly develop a web application.

How developers use ExpressJS and Flask
Avatar of Cloudcraft
Cloudcraft uses ExpressJSExpressJS

Express.js is the workhorse of the backend. It's not the most exciting part of a stack, but it works, is very well documented, and you can find a plugin for almost everything you could possibly want. We also carefully evaluated Koa.js, but decided not to go down this route: fewer plugins, less documentation & answers online. I'm also not personally convinced by the generators yield syntax at all. ES7 async functions looks like a much better bet, and with Promises and Babel I can have that already today.

Avatar of Volkan Özçelik
Volkan Özçelik uses ExpressJSExpressJS

I use express.js for and web apps.

Express is well-known, lightweight, works out-of-the-box, has great middleware support and has minimal learning curve.

It is the best framework to start developing a general Node.js web app.

Avatar of Jack Littleton
Jack Littleton uses FlaskFlask

I use Flask for times when I need to create a REST API that interfaces with other Python code, or there is no specific reason why I'd want to use Node.JS. I prefer Flask because of its small learning curve, allowing me to get started coding as quickly as possible

Avatar of Cloudify
Cloudify uses FlaskFlask

This lightweight web framework enables quick REST API development while enabling easy clustering, and the usage of multiple worker processes required to scale the REST API service to meet high volume requirements.

Avatar of Kent Steiner
Kent Steiner uses ExpressJSExpressJS

I'm fluent in ExpressJS, but over the past two years I have moved to HapiJS. Similar results, but I find Hapi to be more full-featured towards my app, api and service needs. I can operate confidently in both.

Avatar of Promethean TV
Promethean TV uses ExpressJSExpressJS

PrometheanTV utilizes the ExpressJS web application framework to deploy various web applications and services including the Broadcast Center Tool, our video embed service, and our REST API.

Avatar of Merge In
Merge In uses ExpressJSExpressJS

We rely on ExpressJS to serve our content simply, easily, and effectively, without the bloat-ware. Big thanks to StrongLoop for supporting this package.

Avatar of Sail Tactics
Sail Tactics uses FlaskFlask

Service to query NOAA weather forecasts data and service to build tidal current forecast maps using AWS EC2 and Geoserver

Avatar of OnlineCity
OnlineCity uses FlaskFlask

Flask drives our APIs, both the Website APIs and the majority of the REST Messaging APIs

Avatar of papaver
papaver uses FlaskFlask

used flask for a few personal projects. enjoyed its simplicity and ease of use.

How much does ExpressJS cost?
How much does Flask cost?
Pricing unavailable
Pricing unavailable
News about ExpressJS
More news