Mastodon

50k

Communication - Social Networks and Forums

Federated microblogging server.

Flarum

16k

Communication - Social Networks and Forums

Delightfully simple forums.

diaspora*

14k

Communication - Social Networks and Forums

Distributed social networking server.

PixelFed

7.0k

Communication - Social Networks and Forums

Ethical photo sharing platform, powered by ActivityPub federation (alternative to Instagram).

HumHub

6.7k

Communication - Social Networks and Forums

Flexible kit for private social networks.

Redlib

3.4k

Communication - Social Networks and Forums

An alternative private front-end to Reddit, with its origins in Libreddit.

phpBB

2.1k

Communication - Social Networks and Forums

Flat-forum bulletin board software solution that can be used to stay in touch with a group of people or can…

Elgg

1.7k

Communication - Social Networks and Forums

Powerful open source social networking engine.

Friendica

1.7k

Communication - Social Networks and Forums

Social Communication Server.

MyBB

1.2k

Communication - Social Networks and Forums

Free, extensible forum software package.

OSSN

1.2k

Communication - Social Networks and Forums

Social networking software that allows you to make a social networking website and helps your members build…

Simple Machines Forum

729

Communication - Social Networks and Forums

Free, professional grade software package that allows you to set up your own online community within minutes.

qpixel

437

Communication - Social Networks and Forums

Q&A-based community knowledge-sharing software.

BuddyPress

247

Communication - Social Networks and Forums

Powerful plugin that takes your WordPress.org powered site beyond the blog with social-network features lik…