Mastodon in the browser

Mastodon is a microblogging network that runs in the browser, with no download or setup on your computer. The current server release is 4.7.2, published by Mastodon gGmbH. Instead of one company running one giant site, thousands of independent servers run the same open-source software and talk to each other, so a person on one server can follow, reply to and boost posts from people on another.

How Mastodon works

Every Mastodon server (people often call it an instance) is run by someone: a volunteer, a non-profit, a university, a newsroom or a hobby group. Each one sets its own rules, moderation policy and sign-up process. Your account belongs to the server you register on, and your address looks like an email address: a user name plus the server name. Because the servers federate, the choice of server decides who moderates your space and what your address looks like, not who you can talk to. That is the main difference from X (Twitter), Threads or Facebook, where a single company owns every account, the ranking of the feed and the rules for everyone at once.

The home timeline is chronological and shows posts from accounts you follow. There is no ad-driven algorithm deciding what you see first; hashtags, lists and the local and federated feeds are how you discover new people.

Choosing a server

The Open button on this page leads to the official directory at joinmastodon.org/servers. It lists servers that have agreed to the project's moderation standards, grouped by language, region and topic. A few things worth checking before you register:

• the server rules and who runs it — a clear "about" page is a good sign;
• whether sign-up is open, needs approval or is invite-only;
• the language and topic, since the local feed shows what that community posts;
• how moderation is described and which servers it blocks.

An account on one server is not an account everywhere: you sign up separately on each server you want to post from. Mastodon lets you move to another server later and redirect your followers, so your initial choice is not final.

Licence and source code

Mastodon is free software under the GNU AGPLv3 licence. The source code is public on GitHub, so anyone can run a server, audit the code or build on it. Using Mastodon is free of charge; servers are usually funded by donations, and some admins ask members to chip in.

Apps and requirements

The web interface works in any current desktop or mobile browser — there is nothing to install. On Android you can use the official Mastodon app or a third-party client such as Pachli; both have their own pages here. The system requirement is simply a browser with JavaScript enabled.

Safety and privacy

Your posts, direct mentions and media are stored on your server, so its admins can technically read them; direct messages are not end-to-end encrypted. Treat the server like a host you trust with your data. Two-factor authentication is available in the account settings, and you can block or mute accounts and whole servers yourself.

Pros and cons

• Pro: no single owner, no ads in the timeline, a chronological feed.
• Pro: open source, and you can move your account between servers.
• Con: picking a server is an extra step that confuses newcomers.
• Con: search and discovery feel narrower than on centralised networks.