Freedom251 › Social Media APIs
Mastodon
by Mastodon
What Mastodon is
Mastodon is free, open-source software for short-form social networking across independent servers. Each server is operated by an organization or individual and sets its own moderation rules. Users can choose a server or run their own, follow people on other Mastodon servers, and connect with services that implement ActivityPub. The home feed displays followed posts chronologically without algorithmic recommendations or ads, according to Mastodon. Posts support audio, video, images, polls, content warnings, accessibility descriptions, animated avatars, custom emojis, and thumbnail controls. Profiles can be moved to another server without losing followers, according to Mastodon’s servers information. Official iOS and Android apps, a progressive web app, and third-party clients are available. The open API is documented for app development. Self-hosting is possible, though server operation has technical requirements such as email delivery. Mastodon began in 2016 and is headquartered in Berlin, Germany. Its software costs nothing; institutional hosting and support are paid options with unlisted pricing.
Who it suits
Mastodon suits people who want open-source social networking with chronological feeds and server-level moderation. It also fits developers, self-hosters, and organizations seeking API access or managed institutional services.
What it does well
- Free, open-source software
- Independent servers with local moderation
- Chronological feed without ads
- Official iOS and Android apps
- Open API for app development
What to know first
- Choosing a server affects moderation rules
- Self-hosting requires technical operation
- Third-party app experience may vary
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Mastodon software | Free and open-source software; server hosting and operation are managed by independent providers or by the user | Free |
| Institutional hosting and support | Paid hosting, moderation, and support for larger organisations; contact Mastodon to discuss options | On request |
As joinmastodon.org lists them, read 8 Oct 2026. The maker's own page has the final word.
Verdict
Mastodon provides a decentralized social network with portable accounts, broad posting formats, and open development access. Server choice or self-hosting brings operational and moderation responsibilities.
Facts from Mastodon's own pages
- Account portability
- Users can move their profile to another server without losing followers, according to the servers page. · joinmastodon.org, 8 Oct 2026
- API
- Mastodon describes its API as open and well documented and available to everyone for building apps. · joinmastodon.org, 8 Oct 2026
- Apps
- Mastodon provides official iOS and Android apps, a progressive web app, and a directory of third-party apps for mobile, web, and desktop. · joinmastodon.org, 8 Oct 2026
- Custom domain
- Yes · joinmastodon.org, 20 Sept 2026
- Federation
- Users can follow people across Mastodon servers, and Mastodon can interoperate with platforms that implement ActivityPub. · joinmastodon.org, 8 Oct 2026
- Founded
- 2016 · joinmastodon.org, 28 Sept 2026
- Free plan
- Yes · joinmastodon.org, 20 Sept 2026
- Headquarters
- Berlin, Germany · joinmastodon.org, 28 Sept 2026
- Independent servers
- Users join through a server operated by an independent organization or individual, and servers can have different moderation policies. · joinmastodon.org, 8 Oct 2026
- Institutional services
- Mastodon offers organisations paid server hosting, moderation on request, and support contracts for in-house operations teams. · blog.joinmastodon.org, 8 Oct 2026
- Mobile apps
- both · joinmastodon.org, 20 Sept 2026
- Moderation
- Each server sets and enforces its own rules locally, and users may choose a server or host their own. · joinmastodon.org, 8 Oct 2026
- Moderation tools
- Yes · joinmastodon.org, 20 Sept 2026
- Organization
- Mastodon says it began as an open-source project in 2016 and was incorporated as a German gGmbH in 2021; the About page describes a foundation transition process begun in 2025. · joinmastodon.org, 8 Oct 2026
- Posting features
- Posts can include audio, video, images, accessibility descriptions, polls, content warnings, animated avatars, custom emojis, and thumbnail crop controls. · joinmastodon.org, 8 Oct 2026
- Product
- Mastodon is free, open-source decentralized social media software for short-form social networking. · joinmastodon.org, 8 Oct 2026
- Security
- Mastodon requires HTTP signatures to validate that received activity was authored by the actor generating it. · docs.joinmastodon.org, 8 Oct 2026
- Self-hosting
- Users can run Mastodon on their own infrastructure, while the documentation notes that server operation involves technical requirements such as email delivery. · docs.joinmastodon.org, 8 Oct 2026
- Support
- Mastodon lists separate contact addresses for business hosting, security reports, legal matters, and general inquiries. · joinmastodon.org, 8 Oct 2026
- Timeline
- The home feed shows followed posts in chronological order without algorithmic recommendations or ads, according to Mastodon’s site. · joinmastodon.org, 8 Oct 2026
Where Mastodon stands on Freedom251
- Social Media APIs#3 of 20
- Community Platforms#31 of 126