Mastodon

A federated microblogging platform

Project Website Source Code

Added: 2026-02-18

Last Reviewed: 2026-02-18

Yes!

This project appears to be free and open source software.

Guidance

Details

The project is primarily provided under an AGPLv3 license, with the mobile applications provided under a GPLv3 license.

The “joinmastodon.org” website is only source available instead of being FOSS, since no license exists in its repository although it appears this may be reviewed in 2026. The lack of FOSS website has led the Android App to be flagged in F-Droid as promoting or depending on a non-free network service.

The project is managed by Mastodon GmbH, with a US-based 501(c)(3) Mastodon Inc also existing as a strategic overlay and fundraising hub. The project aims to move to an AISBL (International non-profit association seated in Belgium).

The project appears to gain funding from sponsors, donations, grants and from selling merchandise. On the project’s sponsors page they state “Sponsorship does not equal influence. Mastodon is fully independent”.

Details last reviewed 2026-02-18. Our reviews are performed manually, without legal expertise, and therefore may be inaccurate or missing detail relevant for your use. Please don't treat this as legal guidance or assurance of any kind.

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