About 40%: Semrush's June 2025 chart reports Reddit at 40.11% citation frequency across ChatGPT, Perplexity, Google AI Mode and AI Overviews. Wikipedia follows at 26.33% and YouTube at 23.52%. Our cover rounds those reported figures to whole percentages.
The study used 5,000 keywords and over 150,000 unique citations; it was published July 21, 2025. The chart's exact frequency formula and platform weighting are not specified. Semrush labels this metric citation frequency; it does not establish a share of all citations, all AI answers or training data.
The comparisons below retain each study’s platform scope, window and measurement; gaps in the published method remain explicit. Where an engine was not sampled, we say so rather than write a zero.
Why there is no single Reddit percentage
Ask what share of AI answers cite Reddit and you are asking at least four things at once. Each has its own numerator and denominator, and the public studies mix them freely.
- Citation share divides the source links that point at Reddit by all source links in the corpus. Profound's figures are citation shares.
- Answer prevalence divides the sampled responses that contain at least one Reddit citation by all sampled responses. Semrush's figures are answer prevalence.
- Top-source share divides Reddit citations by the citations belonging to a selected subset of leading domains, so every share inside it is larger than the domain's share of the whole corpus. Profound's top-ten tables and Semrush's weekly top-25 lists are subsets.
- Training composition divides Reddit-derived training material by the model's defined training corpus in a stated unit. None of the citation studies measures this, and no engine has published it.
An answer can cite six domains, draw on a page without linking to it, or show no citations at all, so citation share and answer prevalence move independently: a domain can appear in 60% of responses while holding a small share of all links. When someone quotes you a Reddit percentage, ask which of the four they mean before you ask whether it is high.
How often does ChatGPT cite Reddit?
Three public datasets answer this for ChatGPT, and they disagree because they were built differently.
Profound published AI Platform Citation Patterns on June 5, 2025 and updated it in August 2025. Across 680 million citations collected from August 2024 to June 2025, Reddit accounted for 1.8% of ChatGPT citations, second only to Wikipedia at 7.8%. That is a share of all citations in one vendor's corpus, and Profound does not publish how prompts were chosen, how markets and languages were balanced, or the raw data.
Semrush's three-month study of the most-cited domains, published November 10, 2025, re-ran 230,000 prompts across ChatGPT search, Google AI Mode and Perplexity in weekly snapshots from July 14 to October 12, 2025, and analyzed more than 100 million citations. Its ChatGPT finding is the one on our research index: ChatGPT cited Reddit in close to 60% of prompt responses in early August 2025, before that fell to around 10% by mid-September. Even after the drop, Semrush reports Reddit and Wikipedia as ChatGPT's two most-cited domains.
Ahrefs' comparison of June 11, 2025 used Brand Radar data from 957,000 ChatGPT prompts in June 2025 and found that Reddit did not make ChatGPT's top ten domains by mention share.
In one 11-month corpus, then, Reddit was 1.8% of links. In one week of August 2025, it appeared in close to 60% of responses. In one June 2025 sample, it was outside the top ten. All three are honest answers to the question "how often does ChatGPT cite Reddit", and none of them is portable. The 60% figure is a peak, which is why our index dates it and calls it sampled responses.
Semrush offers hypotheses for the September drop, including Google's mid-September removal of its num=100 search parameter and a deliberate move by ChatGPT to cite a few dominant sites less often. We read them as hypotheses. The variation is the finding; the cause is not established.
Does Google AI Overview cite Reddit?
Yes, and in the two datasets that separate Google's AI Overviews from other engines, Reddit was the single most-cited domain there.
In Profound's corpus, Reddit led Google AI Overviews citations at 2.2%, ahead of YouTube at 1.9% and Quora at 1.5%, across the same August 2024 to June 2025 window.
Ahrefs' June 2025 sample of roughly 76.7 million AI Overviews gives Reddit a 7.4% mention share, which Ahrefs defines as how often the model chooses a domain, with Quora at 3.6%. Ahrefs notes that Reddit and Quora rank high only in AI Overviews and miss the top ten in ChatGPT and Perplexity. Mention share and citation share are defined differently and cover different windows, so 7.4% and 2.2% describe the same engine through two lenses; they cannot be averaged.
Pew Research Center's short read of July 22, 2025 adds the reader's side. In browsing data from 900 U.S. adults collected in March 2025, with search results re-collected from April 7 to 17, about 18% of Google searches produced an AI summary. Wikipedia, YouTube and Reddit together accounted for 15% of the sources listed in those summaries; Pew does not break Reddit out, so we do not either. Users who saw an AI summary clicked a traditional result in 8% of visits, against 15% when there was no summary, and clicked a link inside the summary in 1% of visits.
Google AI Mode is a separate product from AI Overviews, and it is what Semrush tracked. There, Reddit sat inside the top five alongside LinkedIn, YouTube and Google's own properties, and its citation frequency rose in late August 2025 and fell again while the top group stayed more stable than ChatGPT's. The short answer to "does Google AI Overview cite Reddit" is yes, in every 2025 dataset we found. Whether it cites your thread is a different question, and nobody has published that.
Reddit AI citations, study by study
The table puts every public figure we use beside its engine, its window and what was divided by what. Read across a row, never down a column.
| Study and window | Engine | What was counted | Reddit figure |
|---|---|---|---|
| Semrush, June 2025, 5,000 keywords and 150K+ citations | ChatGPT, Perplexity, Google AI Mode and AI Overviews | Reported citation frequency | 40.11%, approximately 40%; the leading domain |
| Profound, Aug 2024 to Jun 2025, 680M citations | ChatGPT | Share of all citations | 1.8%, second to Wikipedia |
| Profound, same corpus | Google AI Overviews | Share of all citations | 2.2%, the top domain |
| Profound, same corpus | Perplexity | Share of all citations | 6.6%, the top domain |
| Semrush, Jul 14 to Oct 12, 2025, 230K prompts weekly | ChatGPT search | Share of prompt responses citing Reddit | Close to 60% in early August, around 10% by mid-September |
| Semrush, same study | Google AI Mode | Rank among top-cited domains | Top five; rose in late August, then fell |
| Semrush, same study | Perplexity | Rank among top-cited domains | Listed first; declined slightly in September |
| Ahrefs, June 2025, about 76.7M AI Overviews | Google AI Overviews | Mention share | 7.4% |
| Ahrefs, June 2025, 957K ChatGPT and 953.5K Perplexity prompts | ChatGPT, Perplexity | Mention share | Outside the top ten |
| Pew, March 2025 browsing, 900 U.S. adults | Google AI summaries | Share of listed sources | 15% for Wikipedia, YouTube and Reddit combined |
Perplexity is where Reddit is heaviest in Profound's data, at 6.6% of citations, more than three times its ChatGPT share in the same corpus, and Semrush lists Reddit first among Perplexity's top sources with a slight decline in September 2025. Across the studies, the only pattern that holds is an ordering: Perplexity above Google above ChatGPT in Profound, and Reddit inside the top five on all three engines in Semrush. The levels do not transfer between studies at all.
A Reddit percentage that arrives without its engine, its date and its denominator has not told you anything yet.
Reddit partnerships with Google and OpenAI
On February 22, 2024 Reddit announced an expanded partnership giving Google programmatic access to public posts and comments through the Data API, in Reddit's words to "improve its products and services, including supporting new ways to display Reddit content and providing more efficient ways to train models". On May 16, 2024 Reddit announced that OpenAI "will bring Reddit content to ChatGPT and new products" by accessing the same Data API, which Reddit describes as "real-time, structured, and unique content".
Both announcements establish access. Neither states a training-corpus share, an answer prevalence or a citation rate, and both say Reddit's Data API Terms are unchanged, so content from the API still cannot be used commercially without Reddit's approval. ChatGPT's Reddit prevalence swung from close to 60% of responses to around 10% while the OpenAI agreement was in force, which shows that access and citation are separate facts. A brand shows up in an answer when a specific thread was retrieved and cited for a specific question on a specific day.
How to check a Reddit citation figure before you use it
- Find the denominator. Citations, responses, a top-ten subset and a training corpus give the word "share" four different scales.
- Check the date and the window. The Profound corpus ends in June 2025; the two Semrush studies cover June and July–October 2025, respectively. A study's publication date says nothing about whether its measurement still holds.
- Check the engine and the product. Google AI Overviews and Google AI Mode are different products, and ChatGPT with search on differs from ChatGPT without it.
- Check the prompt set and the geography. A consumer-shopping prompt set and a developer prompt set cite different places, and so do different countries and languages. Neither Profound nor Ahrefs publishes its prompts.
- Separate a citation from a recommendation. A citation is a visibility event. Whether the reader clicked, trusted or bought is a separate measurement, and it needs analytics.
- Keep unmeasured separate from zero. If an engine was not sampled, say so. Do not write down a zero, and do not average an engine you measured with one you did not.
What this means for a brand on Reddit
Google's guide to optimizing for generative AI features, last updated July 10, 2026, says its generative features "are rooted in our core Search ranking and quality systems", that you do not need "new machine readable files, AI text files, markup, or Markdown" to appear, that "seeking inauthentic 'mentions' across the web isn't as helpful as it might seem", and that meeting every requirement does not mean Google "will crawl, index, or serve" the content. It is first-party for Google only, and it matches the citation data. Engines cite pages that answered a real question well, and a Reddit thread is such a page when someone who knew the subject answered a real buyer question and said who they were.
Pew's click rates, 1% on summary links and 8% on traditional results when a summary appeared, mean the visit and the sale have to be measured on their own. Our note on measuring Reddit engagement walks that chain from a useful answer to a business outcome, the measurement section of the field guide shows what we count and what we leave blank, and the research behind how buyers use Reddit before a sales call explains why the thread matters even when the click does not arrive.
When we measure a brand, Reddit AI citations feed two of the five things we measure, recommendation presence and source visibility, and each keeps its own denominator for the reason this article exists. Reading the denominator explains why we never combine engines into one number and why an engine we did not run stays blank rather than zero. We have no client results to publish; a measurement describes a fixed sample of answers on a recorded date and nothing more.
To see where your brand stands, the free Reddit visibility report runs a fixed set of buyer questions on a fixed date and shows the sample behind every score. The participation section of the field guide covers what we do once we know.