We launched 5 projects by using this approach, including a "cash cow" Email Verification Add-on and a recently launched micro-saas Silent Inbox.
Here is how I research subreddits and evaluate them for ideas validation.
When I have an idea to validate I write down at least 5 keywords related to it. Example terms I used last week: “meditation”, “breathwork”, “breathing technique”, “anxiety”, “stress”. Enter one keyword at a time into the search bar and it will give you a list of subreddits where your keyword is mentioned.
Find at least 5 subreddits with people who discussed your topic. Make a copy of my spreadsheet . And collect information about the number of readers. Pro tip: don't waste your time on subreddits with less than 10K readers.
Go to Related Subreddits by User Overlap . You need to check every subreddit you found by searching your terms to get more ideas on when your potential audience is hanging out.
Read posts within each subreddit to see if people might be interested in your project. Add subjective relevance to the spreadsheet, where 10 is for super relevant subreddit.
Once all numbers are added to the spreadsheet, sort your list of subreddits based on the Score it calculates for you.
Congrats, now you are ready to pick the most relevant subreddits, plan content, write a title, research the best time to post, etc.
If you're keen to learn more about the topic, check out our guide on validating project ideas using Reddit.