How to search Reddit and find subreddits with Claude or ChatGPT

Summary#

Reddit's own search works best with its search operators, and Google's site: operator often finds threads Reddit misses. To find subreddits, use the Communities tab, sidebars, r/findareddit or a free finder like RedShip. For keyword alerts, F5Bot is free. To have your agent in Claude, ChatGPT or Cursor do the searching, reading and summing up for you, connect Manifold MCP: hosted, no API keys of your own, pay per call.

How to search Reddit and find subreddits#

Most people ask the same two questions about Reddit: how do I search it properly, and how do I find the right subreddits for my topic? Reddit's search bar is hard to use well, so the usual answers involve search operators, Google, and a lot of tabs.

There is now a third way. When your AI agent can call Reddit through an MCP server, you describe what you want in plain words, and the agent searches posts and comments, finds the communities, reads the threads, and returns a summary with links.

Here is each method, what it is good for, and when to hand the work to your agent.

The methods, compared#

Search Reddit with its own operators#

Reddit's search bar supports field filters and boolean operators. Put no space after the colon.

• subreddit:espresso grinder limits the search to one community.
• title:"cold brew" matches words in the post title only.
• author:name finds posts by one account.
• selftext:refund searches the body of text posts.
• AND, OR and NOT combine terms, and must be written in capitals.

After you search, switch between the Posts, Comments and Communities tabs, and sort by top or new with a time filter. To search inside one subreddit, open it and use its own search bar.

Best for: Fast, free lookups when you already know roughly what you want.

Ask Reddit's AI search#

Reddit has its own AI search, which started life as Reddit Answers. Type a question in the search bar and select Ask, and it replies with a summary of relevant Reddit posts and comments, with citations to the originals. Reddit's help page lists a limit of 50 questions a day for logged-in users, and says the feature summarises Reddit only, not the open web.

Best for: A quick, plain-language answer from Reddit without leaving Reddit.

Search Reddit through Google#

Many people find Google better at surfacing Reddit threads. Add site:reddit.com to any query, or site:reddit.com/r/name to stay inside one community. Google's site: operator documentation explains how it works.

Best for: Older threads, and threads whose titles do not use the words you are searching for.

Find subreddits for your niche#

To find the communities where your audience talks:

• The Communities tab. Search your topic on Reddit and open the Communities tab.
• Sidebars and wikis. Many subreddits list related communities in their About section or wiki.
• Active members. Open the profiles of a few regular commenters and note which other subreddits keep appearing.
• r/findareddit. Describe what you want and members suggest communities.
• A subreddit finder. RedShip's free subreddit finder takes a subreddit or a description of your niche and returns up to 8 public communities, each with a line on why it fits.

Before you post anywhere, check that the subreddit is active and read its rules. Many communities ban links or self-promotion.

Best for: Building a first list of communities by hand.

Get alerts when a keyword appears#

F5Bot watches Reddit, Hacker News and Lobsters for your keywords and emails you when they appear in a new post or comment. The free plan covers keyword alerts by email. Paid plans add advanced filters, AI filtering, feeds, and Slack and Discord alerts.

Best for: Knowing when your brand, a competitor or a topic comes up, without checking Reddit yourself.

Let your agent search Reddit with Manifold MCP#

Manifold MCP is a hosted MCP server at https://mcp.manifoldmcp.com/mcp. There are no API keys of your own to set up, and you pay per call. Connect it to Claude, ChatGPT, Cursor or any MCP client, and your agent can work through Reddit for you:

• reddit_search_subreddits finds communities that match a topic, and reddit_get_subreddit reads a community's details and rules.
• reddit_search_posts and reddit_search_comments search across Reddit for a keyword or phrase.
• reddit_get_post and reddit_get_comments read a thread and its replies so the agent can summarise what people said.
• reddit_get_new_posts returns everything posted in a subreddit in a time window, and says how much of the window it covered.

So instead of running ten searches and opening forty tabs, you ask: "Find the subreddits where people ask about home espresso, check their rules, and summarise the most common complaints about grinders from the last month, with links." The agent picks the calls, reads the threads, and gives you the answer.

Manifold MCP also covers SEO, AI answers, social platforms, ad libraries and leads from the same server, so the agent can check what people say on Reddit and what ChatGPT says about your category in one conversation. Start with 500 free credits, no card required. Top-ups from $10. Pro from $20 a month. See the Reddit tools docs for how each call works.

Honest limits: Reddit search is ranked and never complete, so it is good for finding examples, not for counting every mention. Manifold MCP runs when your agent calls it. It does not send email alerts on a schedule like F5Bot.

Best for: Research you want done for you: finding communities, reading threads, and summarising what people say, inside the agent you already use.

Which method should you use?#

Pick by how often you search and how much reading you want to do yourself.

You need one quick answer. Use Reddit's search with operators, or select Ask to use Reddit's AI search.

Reddit's search cannot find the thread. Try Google with site:reddit.com.

You want a starting list of subreddits. Use the Communities tab and sidebars, or RedShip's free finder.

You want to know when a keyword appears. Set up free alerts with F5Bot.

You want your agent to search, read and summarise Reddit for you. Connect Manifold MCP. It is hosted, needs no API keys of your own, and you pay per call.

Questions people ask#

What is the best way to search Reddit?#

Use Reddit's search operators, such as subreddit:, title: and author:, then switch between the Posts, Comments and Communities tabs. If Reddit's search misses a thread, add site:reddit.com to a Google search. To have an AI agent search and summarise Reddit for you, connect an MCP server such as Manifold MCP.

How do I find the right subreddits for my niche?#

Search your topic on Reddit and open the Communities tab, check the sidebars of communities you find for related subreddits, and ask in r/findareddit. Free finders such as RedShip suggest communities from a description of your niche. An agent connected to Manifold MCP can find subreddits, read their rules and list their recent posts.

Can ChatGPT or Claude search Reddit?#

They can when they have a tool that reaches Reddit. Web search sometimes surfaces Reddit threads. An MCP server gives the agent direct calls to search posts, search comments, find subreddits and read whole threads. Manifold MCP is a hosted MCP server that works in Claude, ChatGPT, Cursor and other MCP clients.

How do I search Reddit comments?#

Search on Reddit and open the Comments tab. Manifold MCP has a reddit_search_comments call, so your agent can search comments across Reddit and return the matches with links.

How do I get alerts when a keyword is mentioned on Reddit?#

F5Bot sends free email alerts when your keywords appear in new Reddit posts or comments, with paid plans for more keywords and Slack or Discord alerts. Manifold MCP does not send scheduled alerts, but your agent can call reddit_get_new_posts to list everything posted in a subreddit since its last check.

Do I need a Reddit API key to use Manifold MCP?#

No. Manifold MCP is hosted, so there are no API keys of your own to set up. Sign in with OAuth or a Manifold API key, start with 500 free credits with no card required, and pay per call after that.