I’m sure a lot of us know most of these already (and it’s unlikely Keebtalk is the first one anyone finds) but I figured a having a list would be useful for finding niche communities and helping new people navigate the community. This is a wiki post; feel free to add to it yourself or make suggestions down below.
Currently very work-in-progress. Please help me flesh out the descriptions and add any I didn’t cover. The non-English forums in particular I’m not familiar with so any help with the descriptions would be greatly appreciated.
Keebtalk
You are here. This is a discussion-centric forum for anyone who is interested in keyboards. Ask us anything, post new things you find, buy and sell boards and parts, and get to know the other users. We’re still a relatively small community but we have lots of experienced regulars who are willing to help or just have fun talking about boards.
Geekhack
One of the OG keyboard forums. This is the primary website for listing interest checks and group buys.
Deskthority
A forum primarily catering to discussion of vintage keyboards. Their wiki is a great source of information, but again primarily focuses on vintage boards.
Reddit lends itself more to sharing photos than discussion, but there are many subreddits for the keyboard community depending on what you’re looking for:
/r/MechanicalKeyboards
The largest English-speaking keyboard forum by number of users. It’s a good place to show off your boards and post your interest checks/group buys. It can be a good source of news since pretty much everything gets posted there, but you basically have to check it every day if you want to use it that way. They also have a fairly large wiki with plenty of useful information, although many of the pages are somewhat outdated.
/r/MechMarket
The largest secondhand market specifically for mechanical keyboards. If you’re looking to buy something you missed the GB for this is the main place to look.
/r/CustomKeyboards
A subreddit dedicated to pictures of customs. A good place to post your latest build and subscribe to if you want your Reddit feed to be full of keyboard pictures.
/r/KeycapDesigners
A great place to visit if you want to float your ideas for keysets to the community pre-IC or if you want to see what people are working on and give feedback.
/r/ErgoMechKeyboards
A subreddit for split and ortholinear keyboards with a heavy focus on creating custom handwired boards.
/r/MechanicalKeyboardsUK
A community specifically for keyboard enthusiasts in the UK. It’s a good place to keep track of meetups or get suggestions on where to get EU-layout boards.
There are many other keyboard subreddits listed on r/mk’s wiki page that are not listed here because they are not very active. If you think any of them deserve special mention, feel free to edit this post and add it to the list.
zFrontier (Chinese)
A Chinese keyboard forum. Somebody please help me write a description, I know basically nothing about it aside from the fact that it’s by far the largest non-English keyboard forum.
OTD (Korean)
Keyboard Lab (Korean)
KBDMania (Korean)
If you’re looking for a forum to discuss keyboards in your native language not listed here, Deskthority has a list of websites you can check out to try to find like-minded people in your country. Many of them are not listed here because they are not specifically keyboard-centric websites.