Nostr vs Mastodon: Protocol Comparison

Introduction

Both Nostr and Mastodon offer alternatives to centralized social media like Twitter. Both are decentralized. Both are open-source. But they’re fundamentally different in architecture, philosophy, and user experience.

This guide explains the key differences between Nostr and Mastodon (and the broader Fediverse), helping you understand which might be better for your needs - or why you might use both.

Quick Comparison

Aspect	Mastodon (ActivityPub)	Nostr
Architecture	Federated servers	Simple relays
Identity	username@server	Cryptographic key pair
Switching Servers	Difficult, some data loss	Seamless, no data loss
Account Creation	Register on a server	Generate keys locally
Server Admin Power	Can ban you from server	Can ignore you, can’t ban identity
Protocol Complexity	High (ActivityPub)	Very low
Maturity	Mature (since 2016)	Young (since 2020)
User Base	~10 million	~2-3 million
Features	Rich, Twitter-like	Growing, basic strong
Server Costs	Higher (full servers)	Lower (simple relays)

The Fundamental Difference

Mastodon: Federated Servers (Like Email)

Federation Model:

You have an account on a specific server (instance)
Your identity is tied to that server (like email: you@gmail.com)
Servers communicate with each other (federation)
Server admins run full social media platforms

Example:

You join mastodon.social
Your username: @alice@mastodon.social
You follow @bob@fosstodon.org (different server)
Servers exchange messages using ActivityPub protocol

Nostr: Simple Relays (Like Radio Towers)

Relay Model:

Your identity is a cryptographic key pair (not tied to any server)
Relays are simple message routers
Clients connect to multiple relays simultaneously
Relays don’t have user accounts

Example:

You generate keys (your identity)
Your public key: npub1abc...xyz
You connect to multiple relays
Relays distribute your signed messages

Architecture Deep Dive

Mastodon (ActivityPub) Architecture

Components:

Instances/Servers: Full-featured social media platforms
Databases: Store user accounts, posts, follows, etc.
Federation: Server-to-server communication
Web Interface: Server provides web UI

How It Works:

You create an account on a server
Post on your server
Server stores it in its database
Server federates to other servers that have your followers
Those servers store copies in their databases
Users on other servers see your post

Server Responsibilities:

User authentication
Content storage
Media hosting
Search indexing
Content moderation
Web interface
Email notifications
Federation logic

Nostr Architecture

Components:

Relays: Simple WebSocket servers
Clients: Applications you use
Events: Signed JSON messages

How It Works:

You generate cryptographic keys (your identity)
Post from any client
Client signs your post
Client sends to relays you choose
Relays distribute to subscribers
Other clients receive and verify

Relay Responsibilities:

Accept signed events
Store events (maybe)
Distribute to active subscribers
That’s it!

Identity and Portability

Mastodon Identity

Tied to Server:

Your identity: @username@server.com
Similar to email
If server shuts down, you lose your identity
Migration possible but incomplete

Migration Process:

Set up new account on different server
Export/import follows and blocked lists
Redirect old account to new one
But: Lose post history, media, exact follower counts
And: People must re-find you at new address

Reality: Most users never migrate. It’s technically possible but practically difficult.

Nostr Identity

Independent Keys:

Your identity: Cryptographic key pair
Not tied to any server/relay
Works with any Nostr client
Completely portable

“Migration”: There is no migration - your identity is portable by design:

Use Client A today
Use Client B tomorrow
Same identity, same followers, same posts
Seamless transition

Reality: Switching clients is as easy as signing in. Your identity follows you.

Content Ownership and Censorship

Mastodon Content Control

Server-Level Control:

Server admin controls your account
Admin can delete your posts
Admin can ban you from the server
Admin can defederate with other servers

Federation Censorship:

Your server can block other servers
Other servers can block your server
Server-level blocklists
Content policies vary by server

User Power:

Choose a server with policies you like
Can migrate (with difficulty)
Limited recourse if banned

Nostr Content Control

No Central Authority:

No one owns your identity (you do, via keys)
Relays can refuse to store your events
But relays can’t ban your identity
You can always use different relays

Relay-Level Choice:

Each relay sets its own policies
You choose which relays to use
Can run your own relay
Multiple relays = redundancy

User Power:

Total identity ownership
Can’t be “deplatformed” from Nostr
Can always be heard somewhere

Server vs Relay: Responsibilities

Mastodon Server Must:

Authenticate users
Store all user data
Host media files
Provide web interface
Handle federation
Moderate content
Send notifications
Implement search
Manage database
Scale infrastructure
Handle spam
Provide API
Legal compliance

Result: Running a Mastodon server is complex and expensive.

Nostr Relay Must:

Accept events via WebSocket
(Optionally) store events
Distribute events to subscribers

That’s it!

Result: Running a Nostr relay is simple and cheap. Can be built in a weekend.

Privacy and Security

Mastodon Privacy

Server Knows:

Your email address
Your IP address
All your posts (including deleted)
All your follows/followers
All your DMs (they’re not e2e encrypted)
Your browsing patterns on the instance

Federation:

Your posts copied to multiple servers
Other server admins can see everything
DMs visible to both server admins

Deletion:

Request deletion
Servers should comply
No guarantee (copies exist elsewhere)

Nostr Privacy

Relays See:

Your IP address (use Tor/VPN)
Your public posts
Your public key
Who you follow (publicly visible)

Relays Don’t See:

Your email (you don’t provide one)
Your identity details (unless you share)
Less metadata overall

DMs:

Encrypted (NIP-04)
Better than Mastodon (admin can’t read)
Not as good as Signal
Improving (NIP-44 coming)

Note: Both protocols have public posts by default. True privacy requires specialized tools (Signal, etc.).

Features and Maturity

Mastodon Features

Current State (Mature):

Rich posting (text, images, video, polls)
Content warnings
Hashtags
Search
Lists
Filters
Bookmarks
Trending
Follows/followers
Notifications
Direct messages
Media handling
Mobile apps

Very Twitter-like in feature set.

Nostr Features

Current State (Growing):

Text posts ✅
Images/media ✅
Reactions ✅
Hashtags ✅
Search ⏳ (improving)
DMs ✅ (basic)
Lightning zaps ✅ (unique!)
Long-form articles ✅
Notifications ✅
Basic features solid ✅

Gap exists but closing rapidly.

User Experience

Mastodon UX

Choosing a Server:

Must pick a server to join
Server choice affects experience
Can be overwhelming for newcomers
“Where should I join?” is common question

Using Mastodon:

Familiar Twitter-like interface
Web UI provided by server
Mobile apps from official and third parties
Consistent experience across servers

Complexity:

Understanding federation
Server policies
Migration challenges

Nostr UX

Getting Started:

Choose a client (no server choice needed)
Generate keys
Must back up private key (critical)
More personal responsibility

Using Nostr:

Experience varies by client
Can switch clients freely
Some rough edges still
Improving rapidly

Complexity:

Understanding keys
Managing security
Choosing relays (though defaults work)

Community and Culture

Mastodon Community

Demographics:

Tech-savvy users
Left-leaning politically
Privacy advocates
Open-source enthusiasts
Twitter refugees

Culture:

Content warnings common
Alt text emphasized
Strong moderation culture
Local server communities
Fediverse > individual instances

Size: ~10 million users across thousands of servers

Nostr Community

Demographics:

Bitcoin/crypto enthusiasts (strong overlap)
Libertarian-leaning
Free speech advocates
Early tech adopters
Protocol-level thinkers

Culture:

Free speech emphasis
Value-for-value (zaps)
Protocol development focus
Less moderation culture
More experimental

Size: ~2-3 million users, growing

When to Choose Which

Choose Mastodon If You Want:

✅ Familiar Twitter experience

Similar features and interface
Mature, polished apps
Established user base

✅ Server community

Local server culture
Shared moderation policies
Community guidelines

✅ Don’t want key responsibility

Password recovery possible
Server handles security
Less personal responsibility

✅ Just want to start posting

Pick server, create account, go
Simpler onboarding

Choose Nostr If You Want:

✅ True ownership

Cryptographic identity
No account to lose
Complete portability

✅ Censorship resistance

Can’t be deplatformed
Always have a voice
Protocol-level freedom

✅ Bitcoin/Lightning integration

Instant value transfer (zaps)
Support creators directly
Financial sovereignty

✅ Maximum portability

Switch clients anytime
No migration needed
Identity independent of infrastructure

Consider Both If:

You value:

Decentralization (both provide this)
Open protocols (both are open)
Alternatives to corporate platforms

You can:

Use both simultaneously
Mastodon for feature-rich social networking
Nostr for censorship-resistance and ownership
Different tools for different purposes

The UK Perspective

Both offer alternatives in the context of UK online regulation:

Mastodon and Regulation

Challenges:

Servers can be regulated
Server admins liable for content
Potentially affected by Online Safety Act
Server locations matter (jurisdiction)

Nostr and Regulation

Position:

Harder to regulate (no central servers)
Relays are simpler (less liability)
Identity independent of jurisdiction
Structurally resistant to centralized control

Learn more about Nostr and UK context

Technical Simplicity Comparison

ActivityPub (Mastodon) Complexity

Specification:

Complex protocol
Multiple document types (Actor, Note, Follow, etc.)
Server-to-server authentication
Object collections
Inbox/Outbox
WebFinger discovery
HTTP Signatures

Implementation:

Months to build a server
Database management
Federation logic
Considerable ongoing maintenance

Nostr Simplicity

Specification:

Events are JSON objects
WebSocket communication
Signature verification
That’s essentially it

Implementation:

Can build basic relay in a weekend
Minimal server requirements
Simple to maintain
Easy to understand

Trade-off: Simplicity means fewer built-in features, but also easier innovation and extensibility.

Migration Stories

From Twitter to Mastodon

“I joined Mastodon.social, found my community, and rebuilt my network. The server culture matches my values, and I appreciate the strong moderation.”

From Twitter to Nostr

“I generated keys, tried three different clients, and love that I truly own my identity. Lightning zaps are amazing for supporting creators.”

Using Both

“I use Mastodon for feature-rich social networking and community. I use Nostr for experimental tech, Bitcoin discussions, and knowing I can’t be deplatformed.”

Conclusion

Nostr and Mastodon solve different problems differently.

Mastodon:

Mature Twitter alternative
Federated servers
Rich features
Established community
Trade: Identity tied to server

Nostr:

Ownership-first protocol
Simple relays
Growing features
Emerging community
Trade: More personal responsibility

Neither is “better” - they’re different tools.

The future of decentralized social media likely includes both protocols serving different needs and preferences.

Ready to explore?

Want to try Mastodon too?

joinmastodon.org - Find a server
Consider: mastodon.social (flagship), fosstodon.org (FOSS), mastodon.online

Both protocols represent the future of user-owned, decentralized social networking. The choice is yours - or use both!

Related Guides:

Nostr vs Twitter - Centralized vs decentralized
How Nostr Works - Technical deep-dive
Getting Started with Nostr - Complete beginner guide