Subreddit AI-Rule Index 2026: 51.2% of the 250 Most Popular Subreddits Prohibit AI-Generated Posts or Comments

51.2% of the 250 most popular public, non-NSFW subreddits prohibit AI-generated posts or comments in their written rules. We read every one of those 250 rule sets through the Reddit data API on 24 September 2026, and 128 communities ban AI content outright. 137, or 54.8%, have at least one rule that addresses AI. Only 9, or 3.6%, have a rule that asks for AI content to be disclosed or labelled. At the very top of Reddit the pattern holds: 27 of the 50 largest communities prohibit it.

That is the short answer to whether Reddit allows AI-generated posts. Reddit as a platform leaves the question to each community, and among the communities most people actually post in, a slight majority have written a ban.

TL;DR: The Subreddit AI-Rule Index reads the written rules of the 250 most popular public, non-NSFW subreddits. On 24 September 2026, 128 of them (51.2%) prohibit AI-generated posts or comments, 137 (54.8%) have a rule that addresses AI content, and 9 (3.6%) require disclosure or labelling. 27 of the 50 largest communities prohibit it. Labels come from a published classifier, and the uncertain cases were checked by hand. The index measures written rules only, not enforcement, and it does not claim a trend.

Not affiliated with Reddit Inc. redditapis.com is an independent third-party API for Reddit data. This index is our own first-party measurement of public rule text. It is not a statement by Reddit or by any subreddit's moderators.

What share of popular subreddits ban AI-generated content?

A little over half. Of the 250 subreddits in the frame, 128 have a written rule that prohibits AI-generated posts, AI-generated comments, or both. That is 51.2%. The number is a share of communities, not a share of users or of posts, and it describes what the rules say rather than what moderators do.

The four figures that make up the index, each measured on the same day against the same 250 rule sets:

• 51.2% of the 250 prohibit AI-generated posts or comments (128 communities)
• 54.8% have at least one rule that addresses AI content (137 communities)
• 3.6% require AI content to be disclosed or labelled (9 communities)
• 27 of 50 of the largest communities by subscribers prohibit AI content (54%)

Read the first number the way the table above sets it out. The number is 51.2. The unit is a share of subreddits, 128 out of 250. The context is written rules that prohibit AI-generated posts or comments, in the most popular public communities, on one date. The interpretation is practical: if you pick a popular subreddit at random and post AI-generated content there, you are more likely than not breaking a rule the moderators wrote down. That is a coin that lands slightly against you, every time.

The gap between the first and second numbers is small, and it matters. 137 communities address AI at all. 128 of them prohibit it. So when a popular community writes a rule about AI, the rule is a ban in the large majority of cases. A rule that asks you to label AI content exists in only 9 communities, and some of those communities ban other AI content in a separate rule.

If you only remember one thing from this page, make it the ratio between those two numbers rather than either number alone. A rule that names AI is, in this population, very close to a rule that forbids it.

How the Subreddit AI-Rule Index was built

The index is one collection run, one classifier and one manual review, all published together so anyone can check the result. Nothing in it comes from a survey, a moderator statement or a third-party list. Every label traces back to rule text that a community's own moderators wrote.

Sample frame. The frame is the first 250 public, non-NSFW subreddits returned by the Reddit data API's popular subreddits listing on 24 September 2026 (UTC, the evening of 23 September in US time), paged through with the listing's own cursor. NSFW communities and any community that was not public were skipped as the listing was read, so the 250 are the first 250 that passed both filters. The frame is stored inside the snapshot, name by name, so a later run can be compared like for like rather than against a different set of communities.

Collection. For every subreddit in the frame we called the subreddit rules endpoint once. That endpoint returns each rule a community has written: its title, its description, what it applies to (posts, comments or both), and the time the rule entry was created. All 250 of 250 calls succeeded, with 0 errors. Only public rule text was stored, and only for rules that mention AI.

Classification. A rule enters the index only if its title, or a sentence or list item in its description, names AI. The pattern covers the term AI itself, large language models, named generators such as ChatGPT, Midjourney, Stable Diffusion and DALL-E, and phrases like machine-generated and AI-generated. The sentence that names AI is then read for two things:

• Prohibits: the sentence, or the rule title it sits under, bans or removes the content. Wording like No AI, AI-generated content will be removed, or must be written by you all land here.
• Disclosure: the sentence asks for the content to be disclosed, labelled, flaired or tagged.
• Mentions: AI is named without a ban and without a disclosure requirement.

A rule whose title names AI is judged on its title plus its whole description, because a rule titled No AI Content means exactly that regardless of the examples underneath.

Manual review. Automated labels were checked in two ways before publication. A random sample of 25 labels was re-read by a person, and every subreddit whose only AI rule came back as a mention, 14 in total, was reviewed in full. The review changed 11 labels. That is covered in its own section below, because it is the part of the method that most affects the headline.

What it does not claim. The index measures written rules only. It does not measure enforcement, it does not claim an adoption trend, and it describes the most popular communities rather than Reddit as a whole. Each of those limits has its own section further down.

Every summary number on this page was rebuilt from the 250 per-subreddit rows before publication, rather than read from a stored total. The rebuilt counts matched the stored summary exactly: 137 with any AI rule, 128 prohibiting, 9 with a disclosure rule, and 27 prohibiting among the largest 50. If you only take one number from a dataset, it should be one you can rebuild from its rows.

The 50 largest subreddits and their AI rules

This is the table most people come for. It lists the 50 largest subreddits in the frame, ranked by the subscriber count the API returned on 24 September 2026, with the label each community's rules received and the title of the rule the AI clause sits under.

Three things stand out when you read down the table rather than across it.

• Dedicated AI rules are only part of the picture. r/DIY, r/movies, r/travel, r/interestingasfuck, r/nextfuckinglevel and r/BeAmazed have a rule whose title is about AI. Many of the other prohibiting communities fold AI into a rule about spam, effort, reposts or relevance.
• Rule titles can hide the ban. r/personalfinance's AI clause sits under a rule titled Unhelpful or disrespectful, and r/TwoXChromosomes' sits under Relevance. Neither title says AI. Both rules remove AI content.
• The no-rule communities are not a single type. News, science, sports, pets and nostalgia communities all appear among the 23 with no written AI rule. There is no single topic that explains which side a community lands on.

The table is also a Dataset in the page's structured data, so the same 50 rows are available to any tool that reads schema.org markup. If you want the rows for your own watchlist rather than the popular set, the subreddit rules API guide shows the single call that returns a community's full rule set.

Which of the largest subreddits prohibit AI content?

Of the 50 largest subreddits in the frame, 27 prohibit AI content in their written rules. The 10 largest of those 27, by subscribers:

• r/funny, 67.6 million subscribers, AI-generated content named in its first prohibition beside social-media screenshots
• r/AskReddit, 59.7 million, AI covered by Rule 11 on spam and machine generated content
• r/worldnews, 47.6 million, a rule against ChatGPT bots and copy-paste bots
• r/gaming, 47.3 million, AI named under a relevance and meme-template rule
• r/Music, 38.6 million, a rule against low-effort, hastily written or AI content
• r/movies, 37.7 million, a dedicated rule titled AI Generated Garbage
• r/memes, 36.0 million, AI covered by the rule that you only post memes you made yourself
• r/pics, 33.5 million, AI images named alongside screenshots
• r/DIY, 27.5 million, a dedicated rule titled No AI Content
• r/videos, 26.9 million, a rule against low-effort AI-generated content

The two largest communities in the frame both prohibit AI content. r/funny, the largest, names AI-generated content in the same sentence as social-media and messaging screenshots, which tells you how the moderators think of it: as a class of content that is not what the community is for, rather than as a technology problem. r/AskReddit, the second largest, covers it inside Rule 11, which is about spam, machine generated content and karma farming. That framing treats AI content as a form of manipulation.

At 27 of 50, prohibition is the majority position among the largest communities by four communities. That is a slightly higher share, 54%, than the 51.2% across all 250. It would be easy to over-read that difference, and we will not: a gap of under three points between a group of 50 and a group of 250 is not evidence that size drives the decision. What it does show is that the biggest communities are not the permissive exception some people assume.

Which large subreddits have no written AI rule?

23 of the 50 largest subreddits have no written rule that names AI. The 10 largest of them, by subscribers:

• r/todayilearned, 41.7 million
• r/aww, 37.9 million
• r/science, 34.6 million
• r/news, 31.6 million
• r/books, 27.3 million
• r/nottheonion, 26.1 million
• r/mildlyinteresting, 25.4 million
• r/dataisbeautiful, 21.8 million
• r/Damnthatsinteresting, 20.6 million
• r/technology, 20.6 million

No written AI rule is not the same as permission. Several of these communities have rules about sourcing, originality or topic that would remove most AI-generated posts on other grounds. r/todayilearned expects a verifiable fact with a source. r/dataisbeautiful expects a visualization of real data. r/news and r/nottheonion expect links to published articles. A community can have no AI rule and still be a poor place to post generated content, because the rules it does have already exclude it.

The honest reading of an empty result is narrow. It tells you the moderators have not written a rule that names AI. It does not tell you what they think of AI content, whether AutoModerator filters it, or whether a post would survive. For those questions the only instrument is to post and read back, which the shadowban and removal guide covers.

What the rules actually say, in the moderators' own words

A label is a summary. The rule text is the evidence. Here is the sentence that names AI in the rules of 14 of the largest prohibiting communities, quoted from what the rules endpoint returned on 24 September 2026. Reading them together shows how wide the range of wording is, and why a keyword search on its own would miss so many of them.

• r/funny: "AI-generated content of any kind is forbidden." The strictest wording in the top 10, and it applies to posts.
• r/gaming: "No AI slop." Three words inside a rule about content that is not directly gaming related or is a generic meme template.
• r/movies: the rule titled AI Generated Garbage targets people "using AI and trying to pretend it's a real user", which frames the problem as deception rather than quality.
• r/memes: "Do not post AI-generated memes", under the rule that you only post memes you made yourself.
• r/pics: "We do not allow AI-generated images of any kind."
• r/DIY: "AI generated content of any kind is NOT permitted", followed by a list that covers posts, comments, imagery, plans, mock-ups, guides, help replies and bot accounts.
• r/explainlikeimfive: "No Bots/AI." inside a rule that top-level comments must be written explanations, and the rule applies to comments.
• r/LifeProTips: moderators "may remove posts or comments at their discretion for being low-quality, low-effort, or appear to be generated or altered by AI."
• r/interestingasfuck: "No AI or AI-assisted content in any way."
• r/relationship_advice: lists "Posts generated by LLMs or AI such as ChatGPT or Claude" among posts that are not allowed.
• r/travel: "ChatGPT and AI usage is strictly against the rules", and the rule goes on to cover suggesting AI and posting text that AI rewrote or proofread.
• r/MadeMeSmile: "Posts that have staged, fake, or AI content will be removed"
• r/cats: "No low-effort content such as memes or AI-generated or AI-altered images."
• r/buildapc: "Lists generated by AI / LLM may be removed, especially if fixing them is considered more work than starting fresh"

Three patterns run through these sentences:

1. Scope words are strong. "Of any kind", "in any way" and "strictly" appear repeatedly. Where a community has written a ban, it rarely leaves room for light AI use.
2. Assisted counts. r/DIY, r/interestingasfuck and r/travel all name AI-assisted or AI-edited content, not just fully generated content. A post you wrote and then had an AI tool polish is inside these rules.
3. The reason varies. Some rules are about deception (r/movies), some about effort (r/cats, r/buildapc), some about originality (r/memes). The reason matters less than the outcome: in each case the rule makes the content removable.

If you run a brand account or post on behalf of clients, the second pattern is the one most likely to surprise you. Rewriting a human draft with an AI tool is ordinary practice in many marketing teams, and several of the largest communities treat it the same as fully generated content.

Posts, comments or both: what AI rules apply to

Every rule the API returns carries an applies_to field that says whether the rule covers posts, comments or both. For AI rules this matters, because a community can welcome your comment and remove your post under the same rule set, or the other way round.

The largest prohibiting communities show all three patterns:

• Posts only. r/funny, r/gaming, r/memes, r/pics, r/relationship_advice, r/BeAmazed and r/buildapc apply their AI clause to posts. An AI-generated comment is not covered by that rule, though other rules may still catch it.
• Comments only. r/worldnews applies its rule against ChatGPT bots to comments, and r/explainlikeimfive applies its rule to top-level comments, where the written explanation is the whole point of the community.
• Both. r/AskReddit, r/Music, r/DIY, r/travel, r/interestingasfuck, r/MadeMeSmile and most of the others apply the rule to posts and comments alike.

The distinction is useful for anyone building tooling. A reply bot that drafts comments with a language model is directly inside the rule in r/worldnews and r/explainlikeimfive, and not inside the AI clause in r/funny or r/pics. A tool that submits generated image posts is the reverse. Reading applies_to alongside the rule text is the difference between a check that is roughly right and one that is right.

It is also a reason not to reduce the index to a single yes or no per community. The table gives you the strongest label. The rule set tells you which kind of content that label covers.

What counts as prohibiting AI content in this index?

A subreddit is counted as prohibiting AI content when at least one of its rules either bans or removes AI-generated content, or requires content to be written or made by a person, and that requirement is explicit in the rule text. The label is attached to the rule, and a subreddit takes the strongest label any of its rules received.

The label rules were written before the run and are published in the collection script, so the decision about any single community can be checked by anyone with the rule text. The pattern that decides whether a sentence is a ban includes:

no ... / not allowed / prohibited / banned / removed
do not post / do not use / isn't allowed / zero AI
must be written by you / must be made by a human
human-written / not generated by

The disclosure pattern looks for disclosed, label, flair, tag, must be marked and similar wording. Within one rule the disclosure check runs before the ban check, so a rule that bans AI content and also mentions disclosure, for example as an exception, can be labelled disclosure rather than prohibits. That ordering makes the prohibits count conservative: a ban with a disclosure clause in it is not counted as a ban.

Three edge cases are worth naming, because they are where a reader is most likely to disagree with a label:

• Bot rules. A rule that bans bots and names ChatGPT, like r/worldnews' No chatGPT bots or copy-paste bots, is counted as prohibiting, because an account posting generated text is the content the rule removes.
• Effort rules. A rule against low-effort content that lists AI among its examples, like r/Music's, is counted as prohibiting, because the listed content is what the rule removes.
• Exceptions. A rule that allows AI art only in a megathread was kept as a mention, because the rule permits the content in a defined place rather than banning it.

Edge cases in the largest 50

A few communities in the table deserve a note, because their label is correct under the method and still easy to misread.

• r/ChatGPT is labelled as prohibiting, and it is a community about AI. Its rules allow AI art only if a submission shows something very unique or unusual, and remove some low-value post types. That is a restriction on AI content inside an AI community, not a blanket ban on AI, and the table's rule excerpt, AI Art, points to the rule that carries it. The label reflects what the rule text says about AI content, not what the community is about.
• r/BeAmazed bans AI-generated image and video posts, with an exception. Its rule says mods may allow a real image or video that was AI upscaled. The label is prohibits because generated content is banned. The exception covers enhancement of real footage.
• r/soccer's AI clause is about accounts. It says novelty, bot, AI and other automated accounts need approval and may be removed when they lower discussion quality. The classifier read the removal wording as a prohibition, and the label stands as published.
• r/LifeProTips gives moderators discretion. Content that appears to be generated or altered by AI may be removed at the moderators' discretion. That is a prohibition in effect, written as a power rather than a rule.
• r/personalfinance and r/TwoXChromosomes have no AI in the rule title. Both were among the 11 communities the manual review reclassified, because the AI line is a bullet in a list of content the rule removes.

None of these change a count. They are here because a reader checking the table against a community's sidebar will reach the same questions, and the answer should be on the page rather than in a follow-up.

A related caution applies to every label in the table: a rule can change the day after a snapshot. The label is a reading of the rule text on 24 September 2026, and the rules API returns the current text whenever you need it.

Where does the AI clause sit in a subreddit's rules?

In the popular set, an AI prohibition takes one of three shapes. The shape matters if you are reading rules by hand, and it matters more if you are writing code to read them.

• A dedicated AI rule. The rule title is about AI. r/DIY's No AI Content, r/travel's Absolutely no AI, r/movies' AI Generated Garbage and r/interestingasfuck's No AI. are all this shape. These are the easiest to find and the least ambiguous.
• A clause in a spam or manipulation rule. AI sits beside spam, bots and karma farming. r/AskReddit's Rule 11 is the clearest example: no spam, machine generated content or karma farming. The title names machine generated content, not AI, so a search for the letters AI in rule titles misses it.
• A clause in a quality or relevance rule. AI is one item in a list of low-effort or off-topic content that the rule removes. r/pcmasterrace, r/cats, r/personalfinance and r/TwoXChromosomes are this shape. The rule title often gives no hint at all.

The practical consequence is that a title search is not a rule check. If a tool looks only for AI in rule titles, it finds the first shape and misses most of the second and third. In this index, 11 of the 14 communities the automated classifier first read as merely mentioning AI turned out to be the third shape: AI listed as an item under a rule that removes everything in the list.

If you are building a check that runs before a post goes out, read every rule's description, split it into sentences and list items, and read the rule title that each item sits under. That is exactly what the collection script does, and it is why the manual review was still needed for the list case.

Why so few subreddits have a disclosure rule

Only 9 of the 250 subreddits, 3.6%, ask for AI content to be disclosed, labelled, flaired or tagged. Compared with the 128 that prohibit it, disclosure is a rare choice.

There are practical reasons a moderation team would pick a ban over a label. A disclosure rule needs a flair or a tag to exist, needs posters to set it, and needs moderators to judge whether an unlabelled post was generated, which is the same judgment a ban needs plus an extra step. A ban is a single decision. Research on moderators points in the same direction: in interviews reported by Cornell, moderators described AI content as a threat to quality, to the social dynamics of a community, and to their ability to govern it.

A few details about the 9 disclosure communities help set expectations if you plan to post labelled AI content:

• Disclosure is usually tied to a flair or a tag. A post without the flair can still be removed.
• Some disclosure rules sit beside a ban. A community can require labels on one kind of AI content and prohibit another kind, which is why a single subreddit can carry both labels.
• Disclosure rules are more common where the content is creative. That is consistent with prior academic work, which found AI rules often focus on AI images and cite concerns about quality and authenticity.

The operational takeaway is simple. If your plan assumes that labelled AI content is broadly welcome in popular communities, the written rules do not support that plan. In this population the realistic options are a community that bans it, a community that has not written about it, and a small number that ask for a label.

How accurate is the classifier?

Accurate enough to publish, with its error rate stated. The review had two parts, and both are reported in full.

The random sample. 25 labels were drawn at random from every rule the classifier flagged and re-read by a person against the full rule text. Among the rules the classifier labelled as prohibiting, 18 of 19 were correct. One miss in 19 is an error rate we are comfortable publishing beside the headline, and we would rather publish it than round it away.

The mention-only bucket. The classifier is weakest in one specific place: a list. When a rule says posts of the following types will be removed and then lists AI-generated content as one bullet, sentence-level matching sees a bullet that names AI and no ban word in that bullet. It labels the rule as a mention. So every subreddit whose only AI rule was labelled a mention, 14 in total, was reviewed by hand.

• 11 of the 14 turned out to list AI content under a rule whose text says listed posts are removed or disallowed. They were reclassified as prohibiting.
• 3 of the 14 are genuine non-bans: an exception that allows AI art in a megathread, a rule about bot-run accounts, and a rule about accuracy that names AI.

The 11 reclassified communities are named in the published script as ADJUDICATED_PROHIBITS, so the decision is visible and reversible rather than hidden inside a label. They include r/personalfinance, r/relationship_advice, r/TwoXChromosomes, r/CasualUK and r/3Dprinting.

The review targets the one bucket where the classifier was structurally weak rather than sampling everything evenly. That is a deliberate choice. A uniform sample of 25 would have been unlikely to catch the list problem at all, because only 14 of the 250 subreddits were in the bucket where it occurs.

What the index does not claim

Three limits apply to every number on this page, and each one is a claim we are deliberately not making.

• No adoption trend. Every rule returned by the API carries a created timestamp. That timestamp belongs to the rule entry and survives edits. A spam rule written in 2022 and edited in 2026 to add AI still reads 2022. A chart of rule dates would put some AI clauses years before they were written, so a comparison with earlier years would be wrong. A trend needs two dated snapshots of the same frame, which a re-run of the collection produces.
• Nothing about enforcement. The index reads written rules. How often moderators remove AI content depends on their judgment, on AutoModerator configuration that is not public, and on how obvious the content is. None of that is visible in a rule set, so the index says nothing about it.
• Only the popular set. The frame is the 250 most popular public, non-NSFW communities. It says nothing about the long tail of smaller subreddits, which may behave very differently. It also excludes NSFW communities by design.

It would have been easy to publish a year-over-year line. The data to draw one was sitting in the snapshot. The line would have been wrong, so it is not here. If you see a number elsewhere claiming this index shows AI rules growing, it did not come from this page.

What moderators are saying about AI content in 2026

The rules in the index are the formal end of a conversation that moderators are having in public. Reading that conversation explains why so many rules take the shapes they do.

In r/devops, the moderators asked their community before writing a rule, and the proposal was not a dedicated AI rule. It was a broader low-effort rule that would include AI-generated posts, which is exactly the third shape described above:

In r/ModSupport, where moderators help each other, a moderator with no AI rule yet asked peers how they handle AI-generated content, and the thread became a comparison of approaches:

Cornell researchers who interviewed moderators, covered in the research section below, grouped their concerns into three, and the threads above read the same way:

• Quality: generated posts that add nothing a reader could not get elsewhere
• Social dynamics: generated posts and replies changing how people in a community talk to each other
• Governability: moderators unable to prove a post was generated

The press has covered the same concerns from outside. Ars Technica reported on moderators working to keep AI slop off their communities:

Ars Technica

@arstechnica

Reddit mods are fighting to keep AI slop off subreddits. They could use help. https://t.co/yyrdFt6Yy6

Tom's Hardware covered r/programming, a large technical community outside our popular frame, deciding to ban AI LLM content entirely:

Tom's Hardware

@tomshardware

The largest programming community on Reddit just banned all content related to AI LLMs — r/programming is prioritizing only high-quality discussions about AI https://t.co/2IJHwNI8Ms

And for a reader's view of why this matters, this walkthrough of spotting AI-written posts on Reddit shows the problem from the other side of the rule:

Reddit is (Increasingly) Fake. Here's How to Spot AI Posts.

Neon Sharpe

Opinion writers have made the broader case too, with PCMag arguing that Reddit is becoming an AI slopfest. None of these sources measure the popular set, and none of them change a number in the index. They are here because they explain the language in the rules: quality, effort, authenticity and spam are the words moderators reach for, and those are the rule titles AI clauses sit under.

What earlier research found about subreddit AI rules

The most thorough prior work on this question is an academic study by Travis Lloyd, Jennah Gosciak, Tung Nguyen and Mor Naaman at Cornell, AI Rules? Characterizing Reddit Community Policies Towards AI-Generated Content. It collected rules across a very large set of public subreddits and built a taxonomy of AI rules.

Its qualitative findings line up with what the popular set shows:

• AI rules are more common in larger subreddits. The popular set is, by construction, large communities, and a majority of them address AI.
• Rules often focus on AI images. Several of the largest prohibiting communities in our table, r/pics, r/BeAmazed and r/cats among them, name images or visual content specifically.
• Rules cite quality and authenticity. That matches the rule titles in the table: low effort, relevance, standards for quality, made yourself.

A follow-up paper from the same group, reported by the Cornell Chronicle, interviewed moderators directly and found them concerned about content quality, social dynamics and how hard AI content is to govern.

What the Subreddit AI-Rule Index adds is narrower and more current. It is one dated read of the communities most people actually post in, with the label for each community published beside the rule title it came from, and a stated error rate. The academic work is the better source for the long tail and for why communities write rules. This index is the better source for which popular communities have a ban on the page today.

What the numbers mean if you post on Reddit or build an agent that does

If you post on Reddit, whether as a person, a brand or through automation, the index changes one default. Before this, a reasonable assumption was that AI content is fine unless a community says otherwise. In the popular set, a slight majority of communities do say otherwise, and they often say it inside a rule whose title does not mention AI.

For a person posting by hand, the practical steps are short:

• Read the whole rule set, not the titles. AI clauses sit inside spam, effort and relevance rules.
• Treat an AI rule as a ban until the text says otherwise. 128 of the 137 communities that address AI prohibit it.
• Look for a flair requirement if the rule asks for disclosure. Only 9 communities in the popular set take that route.

For anyone building an agent or a tool that posts or comments, the index is a warning about scale. A tool that posts generated text into popular communities without reading their rules will be breaking a written rule in roughly half of them. That is a product problem, a reputation problem for whoever the tool posts for, and exactly the kind of thing a rules check at submission time prevents. The Reddit bot rules guide covers what automation is allowed at the platform level, and the AI agents guide covers wiring Reddit data into an agent.

Reddit's own sitewide rules help explain why the answer is per community. The eight Reddit Rules do not mention AI at all. Rule 2 tells people to abide by community rules and to participate authentically, and Rule 5 tells them not to mislead others. The platform sets the frame, and the communities write the specifics, which is why a per-community index is the only way to answer the question for the places you actually post. The Moderator Code of Conduct governs how those community rules are written and applied.

AI rules, bot rules and spam filters are different things

Three different mechanisms can remove AI-generated content on Reddit, and the index measures only one of them. Keeping them apart avoids most of the confusion in discussions about whether Reddit allows AI content.

• Community AI rules. Written by moderators, visible in the rule set, and returned by the rules endpoint. This is what the index measures. 128 of the 250 popular communities have one that prohibits AI content.
• Bot and automation rules. Some communities ban automated accounts regardless of what they post. A bot rule and an AI rule overlap when the bot posts generated text, which is why r/worldnews' rule against ChatGPT bots counts as a prohibition. Platform-level guidance on automation is covered in the Reddit bot rules guide.
• Filters. Reddit's sitewide spam filter and each community's AutoModerator configuration run before any person sees a post. AutoModerator rules live in a wiki page only moderators can read, so no rules endpoint can show them. A post can break no written rule and still be filtered.

The practical order of checks follows from this. Read the written rules first, because they are public and cheap to read. Respect the community's stance on automation if you are posting through a tool. Then read your post back after submission, because the filter layer is invisible until it acts. The monitoring guide covers reading back what you posted.

A pre-post checklist for 2026

For teams that post on Reddit regularly, whether for their own product or for clients, here is the checklist the index suggests. Each item comes from a finding above.

• Pull the full rule set, not the sidebar summary. One call to the rules endpoint returns every rule with its description. The sidebar often shows titles only, and titles hide most AI clauses.
• Search descriptions for AI, LLM, ChatGPT and machine generated. Then read the rule title that each match sits under.
• Treat assisted content as AI content. Several of the largest communities name AI-assisted, AI-edited or AI-proofread text explicitly.
• Check applies_to. A comment-only AI rule does not cover your post, and a post-only rule does not cover your comment, though other rules may.
• Look for a flair if the rule asks for disclosure. Only 9 of 250 communities take that route, so it is easy to miss when it applies.
• Do not read silence as permission. 113 communities have no written AI rule and may still remove low-effort content under other rules.
• Store the label with its date and re-check on a schedule. Rules change, and a cached label without a date cannot tell you when it went stale.
• Read back after posting. Written rules are one layer of three. The filter layer only shows itself afterwards.

A team that follows the first seven steps is working from the same evidence the index is built on. The eighth step is the part no index can do for you.

How to check a subreddit's AI rule through the API

The same logic that built the index works for a single community in one call. Fetch the rules, keep the ones that name AI, read the sentence that names it, and store the label with the date.

curl -s "https://api.redditapis.com/api/reddit/sub/DIY/rules" \
  -H "Authorization: Bearer $REDDIT_APIS_KEY"

The response carries a rules array. Each rule has a name, a description and an applies_to field that says whether it covers posts, comments or both. A minimal check in Python. It is a simplified version of the index's classifier, with shorter patterns, so it can disagree with the published labels on edge cases; the full patterns and the manual adjudication list are in the collection script:

import re, requests

AI = re.compile(r"\bA\.?I\.?\b|\bLLMs?\b|chat ?gpt|machine[- ]generated|ai[- ]generated|midjourney|stable diffusion", re.I)
BAN = re.compile(r"\bno\b|not allowed|prohibit|\bbann?ed\b|removed?|do not (post|use)|written by (you|a human)", re.I)
LABEL = re.compile(r"disclos|\blabel|\bflair|\btag(ged)?\b|must be marked", re.I)

def ai_label(sub, key):
    r = requests.get(f"https://api.redditapis.com/api/reddit/sub/{sub}/rules",
                     headers={"Authorization": f"Bearer {key}"}, timeout=30)
    r.raise_for_status()
    best = None
    for rule in r.json().get("rules", []):
        title, desc = rule.get("name") or "", rule.get("description") or ""
        units = [title] + re.split(r"(?<=[.!?])\s+|\n+", desc)
        hits = [u for u in units if AI.search(u)]
        if not hits:
            continue
        if AI.search(title):
            hits = [title + " " + desc]
        if any(LABEL.search(u) for u in hits):
            label = "disclosure"
        elif any(BAN.search(u) for u in hits) or BAN.search(title):
            label = "prohibits"
        else:
            label = "mentions"
        order = {"prohibits": 3, "disclosure": 2, "mentions": 1}
        if best is None or order[label] > order[best[0]]:
            best = (label, title)
    return best or ("no written AI rule", None)

Two cautions apply to any automated check, and both come straight from the manual review:

• A mention is not proof of permission. If the check returns mentions, read the rule. In the index, 11 of 14 mention-only communities turned out to ban AI content through a list.
• Store the date with the label. Rules change. A label without a date cannot tell you whether it is still true next month.

The rules endpoint docs list every field the response carries, and the rules API guide walks through the full response. For posting limits beyond AI rules, such as karma and account age, see what it takes to post in the top subreddits.

How to re-run the Subreddit AI-Rule Index yourself

The index is designed to be repeated. A second snapshot, taken the same way on a later date, is the only honest route to a trend, and it is cheap to produce.

The run has four layers:

• Frame. Page the popular subreddits listing, skip NSFW and non-public communities, and keep the first 250 names. Store the list with the snapshot. See pagination for the cursor mechanics.
• Collect. Call the rules endpoint once per name. Retry on 429 and 5xx responses with a backoff, which the rate limit guide covers. Record any error as an error, never as a subreddit with no rules.
• Classify. Apply the same sentence-level patterns and the same title rule. Then review every mention-only subreddit by hand, because the list case will reappear.
• Publish. Write the frame, the per-subreddit rows, the errors and the summary to one JSON file named with its date.

python3 collect.py snapshot-2026-12-24.json 250

When you compare two snapshots, compare them on the same frame. The popular listing changes over time, so the second run's top 250 will not be identical to the first. Compare the communities present in both runs, and report the frame change separately, or the trend will partly measure which communities became popular rather than which rules changed.

The cost of a run is one rules call per community plus a handful of listing calls, so a 250-community snapshot is a few hundred requests. Current rates are on the pricing page. If you want the size data alongside the rules, the subscriber count guide covers reading subscribers from the same listing.

What the index looks like across the whole frame

Every one of the 250 subreddits in the frame lands in exactly one of three groups. This split is useful because it shows the size of the population that has not written anything about AI yet.

• 128 prohibit AI content. They have at least one rule that bans or removes AI-generated posts or comments.
• 9 have an AI rule but no prohibition. Most of these ask for disclosure. 3 are the genuine non-bans the manual review kept: an AI-art megathread exception, a bot-account rule and an accuracy rule.
• 113 have no written AI rule. Nothing in their rule text names AI.

The 113 are worth a second look, because they are where change would show up first in a later snapshot. A community with no rule is the only kind that can move into the index for the first time. A re-run that finds some of the 113 have written a ban, compared on the same frame, is the cleanest possible evidence of adoption.

It is also worth being clear about what the 9 middle communities are not. They are not communities that welcome AI content. A disclosure rule sets a condition on AI content, and a mention can be an exception inside a stricter rule. Nothing in the frame is a rule that invites it.

Reading the headline number correctly in 2026

The headline, 51.2%, will be quoted without its context, so it is worth stating once what it can and cannot support.

It can support these statements:

• A slight majority of the most popular subreddits prohibit AI-generated content in their written rules.
• Most popular communities that write about AI ban it. 128 of 137.
• Disclosure rules are rare in popular communities. 9 of 250.
• The largest communities are not more permissive. 27 of the 50 largest prohibit it.

It cannot support these statements:

• Half of Reddit bans AI. The frame is the 250 most popular communities, not all of Reddit.
• AI rules doubled or grew. There is no trend in a single snapshot.
• Moderators remove AI content half the time. Enforcement is not measured.
• The other half allow AI content. 113 communities have no written rule, which is silence, not permission.

The number grammar we used throughout is the safest way to quote it: the number, then its unit, then its context, then what it means. 51.2%, of the 250 most popular public non-NSFW subreddits, that prohibit AI-generated posts or comments in their written rules on 24 September 2026, which means AI content is more likely than not against the rules in a popular community picked at random.

If you moderate a community: what the popular set suggests about writing an AI rule

The index is mostly read by people who post, but the same rule texts are a useful reference for moderators deciding what to write. Nothing here is a recommendation about whether to ban AI content. That is each community's decision. What the popular set does show is which wordings leave the least room for argument.

• Say what counts. The clearest rules in the table name the forms they cover. r/DIY lists posts, comments, imagery, plans, mock-ups, guides, help replies and bot accounts. A rule that lists its scope is easier to enforce and easier for posters to follow than a rule that says No AI and stops.
• Say whether assisted content is covered. r/travel and r/interestingasfuck state that AI-assisted or AI-proofread content is included. Without that sentence, a poster who had a tool tidy up their own writing can reasonably argue the rule does not apply.
• Put AI in the title if the rule is mostly about AI. 11 of the 14 communities the classifier first read as mentions had their ban inside a list under a general rule. Posters skim titles, and a ban hidden in the fourth bullet of a relevance rule is a ban many of them will miss.
• Set applies_to deliberately. A comment-only rule, like r/worldnews', is a real choice. If you intend a rule to cover both posts and comments, check that the rule is set that way, because the field is what tools and the API read.
• Decide between a ban and a label, and say which. Only 9 of 250 communities ask for disclosure. If your community wants labelled AI content rather than none, name the flair or tag in the rule so a poster can comply at submission time.

Moderators in r/ModSupport have been comparing approaches in public, and one recurring problem is proof: a rule is easy to write and hard to enforce when a poster says they wrote something themselves. A rule with a clear scope and a clear remedy does not solve that problem, but it narrows the argument to whether the content is generated, rather than whether the rule covers it.

For researchers, the index is a different kind of resource: a dated, per-community reading of rule text with its classifier and adjudication published. It is small compared with the academic datasets and deliberately narrow, which makes it easy to re-run and compare. If you are studying how popular communities respond to generated content, a series of these snapshots taken the same way is a cleaner longitudinal source than rule creation dates, for the reasons set out in the section on what the index does not claim.

For builders, the index is a reminder that rule text is structured data that is cheap to read. The same call that returned the rules for this page returns them for any public community, and the data API overview covers the other surfaces that sit beside it.

Using the index in a workflow

The index is most useful as a starting list rather than as an answer for any one community. Rules change, and a community you care about may have edited its rules since the snapshot. The workflow we would recommend for anyone who posts at scale:

• Start from the table. If the community is in the top 50, the table gives you the label and the rule title to look for.
• Re-check before posting. One rules call returns the current text. Compare it to the label you expected.
• Cache with a date. Store the label and the date of the read, and refresh on a schedule rather than on every post.
• Read back after posting. Written rules are not the only filter. A post that breaks no written rule can still be removed, which monitoring can catch.

For discovery, the subreddit finding guide covers building a candidate list, and the subreddit stats checker gives a quick read on any single community. Pair either with a rules check and you have the same data the index is built on, for the communities that matter to you.

If you are training or evaluating models on Reddit data, the index is also a reminder that community rules are part of the context of any post, alongside the platform's own Data API Terms. A community that bans generated content is one where a generated post is, by definition, rule-breaking content. The AI training data guide covers the data access side.

Methodology summary

For readers who skipped to the end, the full method in one place:

The snapshot, the methodology and the collection script are kept together, and the adjudicated list sits inside the script. Anyone with API access can repeat the run on the same frame and check every label. Get a key and the same endpoint that built this index is yours to point at any community.