Pixelfed is a free and open-source image sharing social network service. The platform distinguishes itself from other image sharing services through its decentralized architecture, meaning user data is not stored on a central server. It uses the ActivityPub protocol, allowing users to interact with other social networks within the protocol, such as Mastodon, PeerTube, and Friendica. Pixelfed and other platforms utilizing this protocol are considered to be part of the Fediverse. The network is made up of several independent sites that communicate with one another, which is roughly comparable to e-mail providers. The parties involved do not all have to be registered with the same provider, but can still communicate with each other. Thus, users are able to sign up on any server and follow others on the other instances.
Much like Mastodon, Pixelfed implements chronological timelines without content manipulation algorithms. It also aims to be privacy-focused with no third party analytics or tracking. Pixelfed optionally organizes its media by hashtags, geo-tagging and likes based on each server. It also allows audiences to be distinguished in three ways and on a post-by-post basis: followers-only, public, and unlisted. Like several other social platforms, Pixelfed allows accounts to be locked, when followers must be pre-approved by the owner.