If you’re considering moving to a new Mastodon instance, something that might be worth knowing about is what instances it blocks, since this will prevent you from interacting with accounts hosted there.
In most cases, this will be a good thing, but when it comes to disagreements between instance moderators that end in mutual, or one-sided server blocks, you might be cut off from people you follow and who follow you.
"Choosing an instance isn't difficult, I think people are overstating that."
Okay, now find an instance that:
* Isn't defederated from some significant portion of my friend group.
* Isn't defederated _from_ by the same.
* Doesn't defederate from major news sources running on their own instances.
* Has reasonable moderation.
* Will actually be here tomorrow and not just fold.
* Has reasonable uptime.
* I can trust to not to keep an unencrypted copy of the database on a personal device.
Considering moving to a new Mastodon instance? Make sure you don't lose any of your connections.
https://stefanbohacek.com/blog/preview-domain-blocks-before-moving-to-a-new-mastodon-instance/
I built a tool that lets you see which contacts (your followers and accounts you follow) you’d lose if you were to move to a new Mastodon instance. It uses data from the fediverse connections explorer that you will need to export first.

The tool also uses the domain_blocks API endpoint (here it is on mastodon.social), which is public by default, but keep in mind that some instances might disable it for privacy reason.
Neither of my two projects uploads any of your data to any servers. All the communication happens in your browser, between you and the instances you have connections on or you put in below.
I hope you’ll find this useful. If you have any questions, feel free to reach out!