( free tool )

Subreddit Finder

Type a topic, product category or audience. We search a year of Reddit posts and show the subreddits where it comes up most, with how active each one is.

Free, no sign-up. Results come from public Reddit data; we keep only an anonymous daily count of lookups.

How the finder ranks subreddits

Matching posts. How many of the past year's most relevant posts on your topic were published there. This is real conversation, not a name match.
Weekly visitors and contributions. Reddit's own activity numbers for the subreddit, so you can tell a busy community from a quiet one.
Comments on matching posts. Where people actually discuss the topic rather than just post links.

Big subreddits are not always the best ones

A huge general subreddit buries a niche question within minutes, while a smaller community about exactly your topic reads every post. For finding buyers, the subreddits with the most matching posts and comments are usually worth more than the ones with the most members. Read a week of posts before you take part, and check the rules with the subreddit rules checker.

Why it matters for AI search

ChatGPT, Perplexity and Google's AI answers cite Reddit threads constantly, and they cite them from the subreddits where a topic is really discussed. The subreddits this tool finds are the ones most likely to feed AI answers about your category.

Questions

How do I find subreddits about a topic?

Type the topic in the box above. The finder searches a year of Reddit posts on it and lists the subreddits where it was discussed most, with weekly visitors and activity for each.

Does it show NSFW subreddits?

No. Posts marked NSFW and user profile pages are left out.

How fresh are the results?

Each topic is searched live the first time and the result is kept for a week, so popular topics load instantly.

Is it free?

Yes, with a daily limit per visitor so the tool stays free for everyone.

More free Reddit tools

Best Time to Post on RedditSee when a subreddit's top posts were published, by day and hour, in your time zone.Reddit Brand Mention CheckerSee which Reddit posts named your brand in the past month, and where.Subreddit Rules CheckerRead a subreddit's rules with self-promotion, link and karma rules flagged.Reddit Markdown FormatterWrite Reddit markdown and see exactly how it will render, then copy it.Reddit Title CheckerCheck a post title against Reddit's limits and the patterns that get ignored or removed.Reddit Self-Promotion CheckerSee whether a comment mentioning your product reads as help or as an ad, and whether it discloses.

Does ChatGPT name your brand when buyers ask about your category? Check it free.

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