Bluesky

Bluesky (abbreviated as Bsky) is an American microblogging social media service. Users can share short posts containing text, images, and videos. It is owned by Bluesky Social PBC, a benefit corporation based in the United States.

Bluesky was developed as a reference implementation of the AT Protocol, an open communication protocol for distributed social networks. Bluesky Social promotes a composable user experience and algorithmic choice as core features of Bluesky. The platform offers a "marketplace of algorithms" where users can choose or create algorithmic feeds, user-managed moderation and labelling services, and user-made "starter packs" that allow users to quickly follow a large number of related accounts within a community or subculture. The AT Protocol offers a domain-name–based handle system within Bluesky, allowing users to self-verify an account's legitimacy and identity by proving ownership of a domain name.

Bluesky began in 2019 as a research initiative at Twitter, Inc., becoming an independent company in 2021. Development for the social app accelerated in 2022 after Elon Musk's acquisition of Twitter and subsequent severing of ties between the companies. Bluesky launched as an invitation-only service in February 2023 and opened registrations in February 2024. Former Twitter CEO Jack Dorsey left Bluesky Social's board in May 2024. The social media platform experienced a surge in activity in November 2024. As of September 2025, Bluesky had 1.5 million daily active users, down 40% from March 2025, when the network had 2.5 million daily active users.