How to choose the right Mastodon instance?
A daunting choice -- but not irrevocable!

Last updated December 11.
A lot of people are looking at the Fediverse as an alternative to Twitter these days. Well, more accurately, a lot of people are looking at Mastodon as an alternative, and Mastodon's part of a much larger ecosystem of interconnected social media sites and services called the Fediverse. But Mastodon's getting the most attention, because it's got a lot of similarities to Twitter, so that's what I'm going to focus on in this post.
There are a lot of good guides to Mastodon, like Danielle Navarro's Everything I know about Mastodon on Notes from a Data Witch, Amanda Quraishi's Mastodon 101, and Per Axbom's A Brief Mastodon Guide for Social Media Worriers. However, all of the ones I've read gloss over the first major decision you face when signing up: what server (aka "instance") to choose? The choice isn't irrevocable – you can migrate your account to another instance and keep the list of who you're following and who's following you – but it's still daunting.
Different instances have different focuses: are geographically focused (sfba.social), identity-based (tech.lgbt), interest-based (mastodon.art), professional (infosec.exchange), a group of friends (friend.camp), or even lipogrammatic (oulipo.social, which doesn't allow the letter 'e' in posts). Others are "general purpose", without a specific focus – like mastodon.social, mastodon.ai, and hachyderm.io.
What instance you're on has a big effect on your experience. For example:
- Instance admins' policies and moderation choices set the norms of the site. @RadioAngel@sunbeam.city points out, moderation can be extremely bad to non-existent on the bigger instances – and a lack of training and rules for moderators can lead to entire instances turning into a dumpster fire overnight. And people of color on instances that aren't well-moderated have a much higher risk of being targeted by harassment.
- And instance admins can read everybody's private messages, so if you're doing anything confidential, you want to be on a site with admins you can trust!
- An instance's "local" timeline (showing all the posts accounts on an instance make) is a good way of finding new people to follow, so it can make sense to choose something that matches your interests (like mastodon.art, fosstodon.social, hci.social, infosec.exchange, social.coop) or physical location (like sfba.social or wien.rocks). Less positively, if you choose an instance that's mostly white techbros, then that's who you'll mostly be exposed to.
- Some instances run forks (variants) like glitch-soc or Hometown that have user experience, privacy, and anti-harassment improvements that Mastodon's lead developer and BDFL (Benevolent Dictator For Life) Eugen Rochko has kept out of the official release.
- Instances can and do block other instances, so if you wind up on an instance that also hosts nazis or TERFs, you won't have access to a lot of the Fediverse.
You can find out some of this information in advance, but it can be time consuming – and there's a lot that's hard to know up front. If you've got friends who are already on Mastodon, ask them what servers they recommend. If not, use sites like fedifinder.glitch.me or debirdify to find out what servers people you're following on Twitter are using and see what they think.
here's a few resources that can help you find different instances:
- joinmastodon.org/servers has a list of servers that have agreed to the Mastodon Server Covenant, which includes "active moderation against racism, sexism, homophobia and transphobia." Bear in mind that this is very high level, and the site's reality may not align with these values – for example if they don't have enough trained moderators, there may still be problems with racism hate speech and harassment. Still, it's something.
- fediverse.party has a much longer list of instances, classified by region and topic.
- mastodon.help's instance search tool includes the ability to search for sites baesd on the text in their site description. You can also specify the most-used language, number of users, connectivity to other sites, and several other terms. For example, here's the results of a search for instances where English is the most-spoken language, mention privacy in their description, have at least 20 active users, and are connected to at least 100 other instances. The results contain a list of the most frequent hashtags, how long the site has been around, usage statistics, and the version of the software (so you can see if it's running glitch or Hometown), and the admin's email. Useful!
- If you're looking for a server near you, fediverse.observer's map and the fediverse.party list are two good options.
- instances.social lets you search by instance size and language. It used to also allow searching by policies (for example, does it allow NSFW content) but that no longer seems to be an option.
Yeah, it'd be a lot easier if a single site provided all of that functionality. Welcome to Mastodon.
You can can also find out some information about a server before you set up an account:
- Servers' "About" pages typically give an overview of what the site's about and list the site's policies (as a list of rules or a code of conduct), and what version of the software the site is using. The most recent version of the software made these harder to find but you can still get there: it's the "Learn More" link on the left-hand side of the web interface, and the ... button on the right sidebar on phones. How intuitive!
One thing to look for on the About page is the site's policy about hate speech and harassment. If they talk about "free speech" in their description, rules, or code of conduct, that's often (although not always) code for an almost-anything-goes attitude. Of course some sites with good policies don't actually enforce them in practice, but sites with bad policies are big red flags. Also useful: many sites include a list of instances they've blocked or limited, along with explanations. This is one of the best ways to see if they're moderating actively – and what they consider cause for blocking. On the other hand, publishing a list of blocked instances can potentially open moderators up to harassment many instances intentionally don't publish the list . - Most servers let you look at the local timeline even without logging in. On the web interface, it's the "local" link on the right-hand-side of the page; on the phone it's the unrecognizable icon on the right hand side below the # and above the globe. Of course, to reduce the risk of harassment and abuse, some servers don't make this available.
- Servers' "explore" pages show the most active posts on the "federated" timeline. I don't find this particularly useful, but in the latest version this is what you see when you visit a site you're not logged into, so maybe there's something I'm missing.
RadioAngel has some good suggestions about what to look for when choosing an instance:
- Do they have limits on how many users can join the instance? (This is in force to keep the mod to report ratio healthy).
- Do they have a dedicated team of mods? Who are they?
- Read their 'About' & 'Limited Servers' sections. Who are they blocking? What are they blocking for?
- How active is the instance? Despite being invite only or limiting registrations temporarily, is there a lot of activity?
If you've got the time, one good option is to set up accounts on multiple instances and experience them first hand. Right now, I'm primarily using @jdp23@indieweb.social as my main public-facing account, but also have accounts on hci.social and scholar.social for my research-y interests, one on wandering.shop that focuses more on writing, and so on. Some Mastodon apps (like Toot on the iPhone or pinafore.social on the web) make it fairly easy to switch between accounts on multiple instances; or you can do what I do and use multiple tabs in your browser.
And keep in mind that you're not locked into your initial choice. If the instance you've chosen isn't working for you, find another one!
Thanks to RadioAngel for the permission to quote their excellent suggestions, and thanks to @sloot@twit.social for catching a big editing error in an earlier version!
Image credit: “Question Mark” by Hana Chramostova licensed under CC1.0 Universal Public Domain license, via PublicDomainPictures.net