Flask (web framework)

Flask
Developer(s)Armin Ronacher
Initial release1 April 2010 (2010-04-01)
Stable release
3.1.1  / 13 May 2025 (13 May 2025)
Repositorygithub.com/pallets/flask
Written inPython
TypeWeb framework
LicenseBSD 3-clause license
Websitepalletsprojects.com/p/flask/

Flask is a micro web framework written in Python. It is classified as a microframework because it does not require particular tools or libraries. It has no database abstraction layer, form validation, or any other components where pre-existing third-party libraries provide common functions. However, Flask supports extensions that can add application features as if they were implemented in Flask itself. Extensions exist for object-relational mappers, form validation, upload handling, various open authentication technologies and several common framework related tools.

Applications that use the Flask framework include Pinterest and LinkedIn.