Nostr vs Bluesky vs Mastodon: full comparison

The three networks people actually compare when they say "alternatives to Twitter" are Nostr, Bluesky, and Mastodon. They share the broad goal of not being a single company's social platform. They disagree on almost everything about how to get there.

This guide is the side-by-side. It is honest about each network's strengths and weaknesses. We built nostr.blog on top of Nostr, so obviously we think Nostr is the right answer for certain users; we also think Bluesky is a better fit for others, and Mastodon for a third group. The decision matters and deserves a clear comparison.

TL;DR. Mastodon is a federation of independent Twitter-like servers with per-server rules. Bluesky is a protocol (AT Protocol) that tries to be federated but is mostly one company today. Nostr is a pub/sub protocol with no servers that matter, only small interchangeable relays. Pick Mastodon if you want server-scoped community governance, Bluesky if you want the smoothest Twitter replacement, Nostr if you want your identity to be uncensorable across any relay.

When you are ready, grab your @nostr.blog address →

The short definition of each

Mastodon launched in 2016. It is a Twitter-like social network built on the ActivityPub protocol. Users sign up on a specific server (an "instance"), which has its own rules, its own admin, and its own moderation decisions. Instances federate with each other so users on different instances can follow each other. If your instance goes down or bans you, your identity and follower list are tied to that instance and do not transfer automatically.

Bluesky launched to the public in 2023. It uses AT Protocol, which the Bluesky team developed. AT has three layers: PDSs (Personal Data Servers, which store your posts), Relays (which aggregate and republish), and App Views (which render feeds). In theory any of these can be run by anyone. In practice, Bluesky PBC (the company) runs the main instance of each, and most users sign up there by default.

Nostr was specified in late 2020 by a developer named fiatjaf. It is a pub/sub protocol over WebSockets with cryptographic signatures. Your identity is a key pair on your device. Relays (small servers) store and forward signed events. No company runs "the" Nostr; the protocol has no central anything.

Head-to-head table

Identity ownership

On Mastodon, your identity is @you@mastodon.social or wherever you signed up. If that instance shuts down, your account is gone. Some instances let you migrate your follower list to a new instance, but the process is awkward and does not cover your post history. In practice most users stay where they started.

On Bluesky, your identity is a DID (Decentralized Identifier), resolvable across PDSs. In theory you could move your account from Bluesky PBC's PDS to a self-hosted one and keep the same handle. In practice almost nobody does this, because the self-hosted PDS stack is fiddly. The option is real, but underused.

On Nostr, your identity is a private key you generate on your own device. It is not tied to any server at all. Any relay that serves your events is interchangeable. If every relay you use disappeared tomorrow, you could publish to new ones and your followers would still find you because they follow your public key, not a server address.

The ranking by "how hard to take away from you" is clear: Mastodon (easy, tied to instance), Bluesky (medium, portable in theory), Nostr (practically impossible because no server has power over users).

Network architecture

Mastodon is federation. A finite number of servers talk to each other. Your server decides what other servers it will accept content from and send content to. Instance-level defederation (one instance refusing to speak to another) is common and has political edges.

Bluesky is a layered protocol. PDS stores posts. Relay aggregates. App View renders. In the default setup, one company provides all three layers. In the decentralized future, these could be independent. As of April 2026, that future is still mostly one company.

Nostr is pub/sub with no central coordination. Clients connect directly to relays. Relays do not talk to each other. You publish to several relays; your followers subscribe to several relays; the union of that gives everyone a reasonable feed. There is no "federation" because there is nothing to federate with; each relay is independent by design.

The simplest architecture is Nostr. The most feature-rich protocol spec is Bluesky. The most established operationally is Mastodon.

Moderation

Mastodon has per-instance moderation. The admin of your instance writes rules and enforces them. Instances block other instances. Content that is legal in one place but prohibited in another can be invisible in half the network. This is both a feature (community scope) and a friction point (you move instances when the rules no longer fit).

Bluesky has centralized moderation by Bluesky PBC, with labeler services that users can opt in to on top. The default experience is closer to Twitter: one platform, one rulebook, user-customizable extra labelers for things like nudity, misinformation, spam.

Nostr has no platform-level moderation. Each relay decides what it accepts. Each client decides what it displays. Each user tunes mute lists. The protocol only verifies cryptographic authenticity, not social acceptability. For users who want curation, responsible clients package together sensible defaults; for users who want nothing filtered, the option exists.

The tradeoff across the three: Mastodon moderation is community-scale and often strict. Bluesky moderation is platform-scale and polished. Nostr moderation is user-scale and uneven.

Monetization

Mastodon has no native monetization. Users link out to Patreon, Ko-Fi, or similar. The ActivityPub protocol does not define a payment primitive.

Bluesky also has no native monetization as of April 2026. The team has discussed it but not shipped it.

Nostr has zaps, the Bitcoin Lightning tip that anyone can send in one tap. A popular Nostr writer can realistically earn a living from zaps alone if their audience values their work enough. No platform cut, no ad intermediary, money moves sender to recipient in seconds. This is a meaningful advantage for anyone whose business model is direct audience support.

The monetization advantage is real and currently unique to Nostr in this comparison. Whether it compensates for Nostr's smaller audience is user-specific.

Adoption and network effect

Honest numbers for April 2026:

• Mastodon: about 2 million monthly active users, stable since the 2022 Twitter migration wave subsided. Heavy in tech, journalism, and academia.
• Bluesky: about 25 million monthly active users, growing, with heavy crossover from Twitter journalists, politicians, and academics.
• Nostr: a few hundred thousand monthly active users, slow steady growth, heavy in Bitcoin, cypherpunk, and independent-developer circles.

For reference: Twitter/X has about 500 million, Meta Threads about 250 million.

If the people you want to reach are journalists or academics, Bluesky has the most of them right now. If your circle is Bitcoin or cypherpunk, Nostr has more. If you are in a specific niche (furry community, academic economists, small tech subcultures), Mastodon often has the densest representation via topic-scoped instances.

Developer ecosystem

Mastodon has a mature API, several hundred apps, decades of federation literature. The technology is well-understood and boring, in the good sense.

Bluesky has a younger but well-documented API. AT Protocol is ambitious; building on it is less rough than raw AT used to be but still more involved than building on Mastodon.

Nostr has the simplest protocol surface of the three. A developer can write a functional Nostr client in a weekend with a websocket library and a SHA-256 implementation. This simplicity is why there are already 10+ Nostr clients, compared to maybe 4 major Bluesky clients at similar maturity. The disadvantage is that there is less convention, so clients disagree on subtle things (tag conventions, specific kind numbers for niche use cases) and the spec sometimes feels like it is moving under your feet.

Who should pick which

Not everyone needs to pick one. Using two or three for a while is the honest advice.

Mastodon is right for you if:

• You want community scope (a specific instance with like-minded people and firm rules)
• You care about ActivityPub compatibility with the rest of the Fediverse
• You are comfortable with instance-level loyalty and potential migration if your instance changes policy

Bluesky is right for you if:

• You want the smoothest Twitter replacement in terms of UX and feature parity
• The audience you want to reach is already there (journalists, academics, politically engaged users)
• You are okay with the current level of centralization in exchange for a polished product

Nostr is right for you if:

• Ownership of identity matters to you above all
• You are in or curious about the Bitcoin or cypherpunk space
• You value the ability to monetize directly via zaps
• You are comfortable with a smaller, more technical community for now
• You want a protocol you can build on yourself without asking anyone for permission

If Nostr is your pick and you want the shortest distance between decision and first post, nostr.blog bundles identity, wallet, and a full web client on one page. You can add a native mobile client later and your identity travels with you.