Mastodon Safety Guide for Parents
What parents need to know about Mastodon, the federated social network where the choice of server (instance) shapes the entire safety experience.
Mastodon is a decentralised, ad-free social network of independently run servers where users post short public updates, positioned as an alternative to X.
Official age
16+
We recommend
16+
Developer
Mastodon gGmbH and independent operators
Risks
4
Overview
Mastodon is the most widely used federated social network in the fediverse. Rather than one central service, thousands of independently run servers (instances) interoperate using the ActivityPub protocol. A child who signs up to a generalist instance like mastodon.social is bound by that instance's rules, but their feed can include posts from anyone on any other instance their server still federates with. Each instance sets its own minimum age, moderation policy, and content rules. The flagship mastodon.social instance currently sets a minimum age of 16, but other instances may allow 13+, 18+, or have no age check at all. There is no single parental supervision tool because there is no single platform to supervise.
How children use it
Older teenagers use Mastodon for tech, art, queer, and academic communities, often as a quieter alternative to X. Many discover it through a friend's invite link to a specific instance. Some join hobby-themed instances - art, gaming, language learning, music - which can be tight-knit and well-moderated, while others end up on barely-moderated instances they found through a search or link. Conversation conventions differ sharply: on some instances, content warnings on every sensitive post are expected, while on others CW culture barely exists. Because the experience is shaped by the chosen instance, a child can move from a calm community to a hostile one simply by changing servers.
Main risks
Recommended privacy settings
Choice of Instance
Location: Sign-up screen -> Choose a server
Set to: Well-moderated generalist instance with a published code of conduct
This is the single most important safety setting on Mastodon. Stick to instances on the Mastodon Server Covenant list for under-18s and avoid any instance that markets itself as 'free speech', 'uncensored', or '18+'.
Default Post Visibility
Location: Preferences -> Other -> Posting privacy
Set to: Followers only
Stops posts appearing on the public timeline of every federated instance. Replies inherit the parent post's visibility, so this is the simplest way to keep a teen's posts from spreading widely.
Discoverability
Location: Preferences -> Public profile -> Suggest account to others
Set to: Off
Prevents the account from being shown in Mastodon's account discovery and search features across instances.
Content Filters
Location: Preferences -> Filters -> Add new filter
Set to: Add keyword filters for adult or distressing topics
Manually filter posts containing specific keywords. There is no built-in adult-content toggle on Mastodon comparable to other platforms.
Direct Messages
Location: When posting -> Visibility -> Direct
Set to: Treat DMs as semi-public
Direct messages on Mastodon are not end-to-end encrypted. Instance administrators on both sides of the conversation can read them. Use only for non-sensitive exchanges.
Parent actions
Pick the instance together using the Mastodon Server Covenant list and read its code of conduct before signing up
Time: 20 minutes
Set default post visibility to 'Followers only' and turn off account suggestions before posting anything public
Time: 10 minutes
Explain content-warning culture and that DMs are not encrypted and can be read by instance administrators
Time: 10 minutes
Agree to talk before joining or moving to any new instance
Time: 5 minutes
Related app guides
If you need to report this
In immediate danger: call 999. For non-emergency police matters, call 101.
Concerned about a child but it's not an emergency? NSPCC helpline 0808 800 5000. Childline for young people 0800 1111.
Myths & facts
Myth: Mastodon now checks ages, so a teenager can't get onto an instance meant for adults.
Fact: Signing up typically just asks for a self-reported birthdate, with no identity or document check behind it, and Mastodon's own developers have said the software isn't built to verify ages. A child can enter any birthdate on many instances, and some instances set no age limit at all.
Myth: All Mastodon instances follow the same rules and moderation standards as well-known ones like mastodon.social.
Fact: Each instance sets its own minimum age, moderation policy, and content rules, and some exist specifically to host material that mainstream platforms remove. Following a friend's invite link to an unfamiliar instance can land a child somewhere far less supervised than the flagship instance most people picture.
Myth: Mastodon being decentralised means no single person or authority is actually responsible for keeping a server safe.
Fact: Each instance has an identifiable operator, often an individual or small collective, who is responsible for moderating their server, enforcing their own code of conduct, and handling reports - a much smaller, differently resourced version of a big platform's trust and safety team. Reporting a problem means contacting that instance's admin directly, alongside CEOP or the police for anything serious.
Age by age
- 11-13
Well below the flagship instance's minimum age of 16, and the federated, multi-admin model is too complex for a child this age to navigate alone. If the interest comes from a hobby community such as art or gaming, look for a same-interest space designed for younger users instead.
- 14-16
Still below the usual minimum age on well-known instances, and only worth considering with close involvement: choose the instance together from the Mastodon Server Covenant list, read its code of conduct, and set default post visibility to followers-only before they post anything.
- 17-plus
Old enough to manage instance choice and moderation settings independently, but it's still worth talking through the fact that direct messages can be read by instance admins on both sides of a conversation, and agreeing they'll mention it before moving to an unfamiliar instance.
Frequently Asked Questions
Related Resources
Sources
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