Table of contents

  • What is Lemmy?
  • What is an instance?
  • How do I join a community from another instance?
  • How can I find interesting communities?
  • Why are image uploads on limited to 100kb?
  • How can I post images hosted on external services?
  • How can I ensure my community on gets found on other instances?
  • How can I take over a community with inactive mods on
  • I’m still lost, how can I get assistance?

What is Lemmy?

One great way to understand Lemmy is to check out this simple infographic (author:

But if you want it in text form:

Lemmy is a link aggregator, in many ways similar to Reddit, but with one key difference - there is no one central authority controlling Lemmy. The code is open source, and more importantly, there are hundreds of Lemmy instances which are all independently run.

Even though instances are independent, they are all part of the Lemmy network, and thus, users of one instance can participate in communities of other instances.

What is an instance?

Lemmy instances are servers which run the Lemmy software. (where this post lives on) is one instance, but there are also many others.

There can be several key differences in instances:

  • Some instances are small and run out of home servers, some instances are large and run on commercial hardware ( is one of the latter)
  • Each instance can define their own set of rules ( rules are visible in the sidebar on our front page)
  • Instances can decide whether downvotes are enabled for their users ( users have the ability to downvote)
  • Some instances may choose to limit community creation to admins only ( allows all users to create communities)
  • Some instances have a tight focus, others are general-purpose ( is the latter!)

If you ever find yourself unhappy with your instance, you are always free to create an account on another one and continue using Lemmy. Unlike centralized platforms, you always have another place to go!

⚠️ Lemmy does not currently support migrating users or communities from one instance to another. Until such a feature is implemented, your post history will remain on your old account when you create a new one on another instance.

How do I join a community from another instance?

The following is up to date as of Lemmy version 0.17.4, but may change in the future.

Option 1: go to the list of communities by clicking the “Communities” link on the top navbar. Open the “All” tab and you will be able to browse and subscribe to any community from other instances that at least one user has previously subscribed to.

Option 2: if you know the exact name of the community you wish to join (for example, !, you can navigate to the search view by clicking the looking glass icon on the top navbar. Enter the exact name of the community into the search box, including the leading “!”: ! If at least one person from has previously subscribed to this community, then you should immediately see a link to open the community and subscribe to it.

Important caveat: if you are the first person to search for a community, then Lemmy will initially tell you that no results were found. Don’t worry, if the community exists, then will begin syncing it and you will be able to successfully search for it again in a couple of minutes.

Important caveat 2: if you are the first user to subscribe to a community from another instance, then historical posts and comments will not be immediately synced. This is a limitation of the Lemmy software currently. However, if old posts start getting some new activity after you’ve subscribed (like a new comment or edit), then that will trigger a sync and the old posts should start showing up for you as well.

How can I find interesting communities?

You have several options!

Why are image uploads on limited to 100kb?

One of the scaling issues so far with Lemmy is multimedia storage. Several instances report growing their storage by significant amounts daily - if grew at that same pace, I would start seeing increased infrastructure bills very quickly (within months, if not weeks).

To help mitigate this, users are asked to use external image hosting providers as much as possible. On, we currently only allow image uploads for images up to 100kb in size.

100kb was specifically chosen as it SHOULD cover most needs for any avatars, and possibly even simple banners for communities.

How can I post images hosted on external services?

For posts, just submit the image URL directly (in other words, copy the image URL into the “URL” field of the post you are creating).

Additionally, for text posts and comments, you can use the following syntax: ![alt text](image url), for example ![ logo]( results in: logo

How can I ensure my community on gets found on other instances?

  • First of all, you should ensure that your community looks welcoming to new users. If your sidebar has useful info and there’s perhaps some activity in the community already, then new users are much more likely to subscribe
  • Once you have your new community set up, your community will soon become automatically visible in our local communities list at, as well as the global community indexes like or
  • If you want even more exposure for your community, I recommend making a post about it in !

How can I take over a community with inactive mods on

  1. Make a post in the community you want to take over
  2. DM me (@sunaurus) 1-2 sentences about what your plans are for the community, and a link to the post you made in the community

If the community you want really has no active mods, then I will be happy to pass ownership to you!

I’m still lost, how can I get assistance?

If you feel like anything in this guide is unclear, or if you have a general question which you believe will be useful to others in the future, please just drop a comment with your question under this post and myself or other helpful members of our community can try and help you out.

If you’re having any issues that you feel are not relevant as a comment here, then feel free to post a thread and tag me in our !support community.

  • Azzu
    1 year ago

    I made a userscript (Lemmy post) which rewrites all links everywhere to always point to your home instance. It helps a lot with subscribing to communities and in general makes browsing the web and finding Lemmy links nicer. Maybe it could be added to the post?