I needed to find subreddits about productivity software.

Simple enough, right? Typed "productivity" into Reddit search. Got r/productivity with 3 million members. Great. But that subreddit is so big that posting anything gets buried in seconds.

What I actually needed were the smaller communities. The ones with 5,000 to 50,000 members where posts actually get seen and discussions happen.

Finding those took me way longer than it should have. Here is everything I learned about discovering subreddits in 2025.

Why Subreddit Discovery Matters

If you are on Reddit for marketing, research, or community building, the subreddits you choose determine everything.

Post in the wrong community and you get ignored or banned. Post in the right one and you get engagement, feedback, even customers.

The problem is Reddit has over 2.8 million subreddits. Most of them are dead. Many are hyper-specific. And the really good ones - the active communities with engaged users - are not always obvious to find.

Method 1: Reddit Native Search (The Obvious Starting Point)

Start with Reddit's built-in search. Type your topic and filter by "Communities" to see matching subreddits.

This works for major topics. Search "photography" and you find r/photography, r/photocritique, r/AskPhotography.

But it fails for niche topics. The algorithm prioritizes subscriber count, so smaller active communities get buried.

Pro tip: After finding one relevant subreddit, check its sidebar. Many communities have "Related Subreddits" or "Similar Communities" sections linking to others in the same space.

Method 2: r/FindAReddit

This is Reddit's own subreddit for finding subreddits. Yes, that exists.

Head to r/FindAReddit and either search existing posts or make your own asking for recommendations. The community is surprisingly helpful.

Example post: "Looking for subreddits about indie game development that are smaller than r/gamedev"

Within a few hours you typically get 3-5 quality suggestions from people who actually participate in those communities.

The downside: it is manual and slow. Good for one-off searches, not for systematic research.

Method 3: Google Site Search

Reddit's internal search is notoriously bad. Google's is better, even for Reddit content.

Use this format:

site:reddit.com/r/ [your topic]

This returns subreddit pages and discussions that mention your topic. Often you discover communities through recommendation threads that Reddit's own search would never surface.

For marketing research, I also search:

site:reddit.com "what subreddit" [topic]

This finds posts where people asked similar questions about finding communities.

Method 4: The Sidebar Chain Method

Once you find one relevant subreddit, use it as a jumping-off point.

Go to the subreddit sidebar (on desktop, or "About" on mobile)
Look for related community links
Visit those communities and check their sidebars
Repeat

This creates a chain of discoveries. One subreddit leads to three more, which lead to nine more.

I have found some of my best niche communities this way - places that never show up in search results but are linked from other established subreddits.

Method 5: Third-Party Subreddit Finder Tools

Several tools exist specifically for subreddit discovery:

GummySearch tracks growing communities and provides analytics on subreddit activity. Their "Growing Communities" dashboard shows daily and weekly subscriber increases.

Subriff provides sortable lists ranked by recent growth percentage. Good for finding communities with momentum.

ReddStats and Redditlist offer category-based browsing and rankings.

These tools are useful but most require subscriptions and focus on analytics rather than pure discovery.

For my own research, I built Wappkit Reddit to search across multiple subreddits simultaneously and filter by engagement metrics. It is more focused on finding posts and conversations, but the multi-subreddit search helps identify active communities quickly.

Has a 3-day trial, then $14/month with code BNWPJRLVJH. Mainly useful if you are doing systematic outreach or research across many communities.

Method 6: Competitor Analysis

If you are researching subreddits for marketing, look at where your competitors post.

Search their brand name or product name on Reddit:

site:reddit.com [competitor name]

Find threads discussing them and note which subreddits those discussions happen in. These are communities already interested in your category.

You can also check competitor websites. Some link to their Reddit communities or mention subreddits in blog posts.

Method 7: User Profile Mining

This one is underrated.

Find users who post helpful content in your niche. Click their profile and look at their comment history. Where else do they participate?

Active users in one subreddit often participate in related communities. Following their trail reveals connections between communities that you would not discover through search.

This is especially useful for finding private or invite-only subreddits. Sometimes users mention them in comments even though they do not show up in search.

Evaluating Subreddit Quality

Finding a subreddit is one thing. Knowing whether it is worth your time is another.

Here is what I look for:

Activity signals:

Posts per day (use Reddit's "New" sort and count)
Comment-to-post ratio (more comments = more engagement)
Upvote patterns (consistent voting vs dead posts)

Community health:

Recent mod activity
Enforced rules (too strict can be bad, no rules is worse)
Mix of question and discussion posts

Size sweet spot: For marketing and outreach, I target subreddits with 5,000-100,000 members. Big enough to have activity, small enough that posts get visibility.

The mega-subreddits with millions of subscribers are brutal for new posters. Your content competes with hundreds of daily submissions.

Organizing Your Discoveries

Do not just find subreddits - track them.

I keep a spreadsheet with:

Subreddit name and URL
Subscriber count
Estimated daily posts
Content style notes
Rule summary
My relevance rating (1-5)

This becomes a research asset over time. When I need to find communities for a new topic, I often discover connections through my existing list.

Common Mistakes to Avoid

Focusing only on big subreddits. The communities with 1M+ subscribers are usually the hardest to get traction in.

Ignoring rules before posting. Every subreddit has different norms. Read them first.

Not lurking before participating. Spend a week reading posts before you comment. Understand the community's tone.

Spamming the same content everywhere. Reddit's spam detection is aggressive. Posting identical content across multiple subreddits gets you shadowbanned.

Quick Action Plan

If you need to find subreddits today:

Start with Reddit search for obvious communities
Check sidebars for related communities
Use r/FindAReddit for specific requests
Run Google site searches for deeper discovery
Track everything in a spreadsheet

For ongoing research, consider a tool that automates multi-subreddit searching. The manual process is fine for one-off discovery but gets tedious at scale.

Found any hidden gem subreddits using these methods? Share them in the comments - always looking for new communities to explore.

How to Find Subreddits: 7 Methods to Discover Reddit Communities in 2025