G2 vs Capterra: which does AI cite?

All 33 review sites together received 81,256 of 7,013,388 citations, or 1.2%. That is about 1 citation in 86. At least one review-site page appeared in 7.0% of cited answers (59,564 of 853,832).

Reddit received 222,751 citations, 2.7 for every review-site citation. The gap is wider on Google AI Mode (3.6 to 1) than on ChatGPT Search (1.6 to 1). Review sites are a real source in AI answers, but a small one.

Ranked by share of review-site citations on both engines, G2 had 21.6% and Gartner Peer Insights had 18.3%. Gartner Peer Insights here means only Gartner's review pages, not its research articles. Three product-testing sites came next: Consumer Reports (11.1%), RTINGS (10.8%) and PCMag (9.0%). Capterra was sixth with 4.7%.

Software Advice and GetApp, which belong to the same company as Capterra, added 2.0% and 1.8%. TrustRadius had 1.3% and Trustpilot 0.9%. Google Maps reviews appeared 71 times. Eighteen smaller review sites shared the remaining 7.2%.

The two engines ranked review sites differently. On Google AI Mode, Gartner Peer Insights had 23.9% of review-site citations and G2 had 20.2%. On ChatGPT Search, G2 led with 23.6%, followed by RTINGS (17.3%) and Consumer Reports (17.2%). Gartner Peer Insights had 10.4%.

G2's lead over Capterra was 3.6 to 1 on ChatGPT Search and 6.1 to 1 on Google AI Mode. PCMag received 7,285 citations on Google AI Mode and none on ChatGPT Search. PCMag's publisher, Ziff Davis, is suing OpenAI. Yelp received 98.6% of its citations on Google AI Mode.

Profound reported that about a third of ChatGPT's review-site citations go to G2. Within the same eight software review sites, we measured 48.4% for G2 on ChatGPT Search and 38.3% on Google AI Mode. So the answer to which review site ChatGPT cites is G2, by a wider margin than the earlier estimate.

A market is a group of buyer prompts about one product or service category on the public Parse index. 56 markets had 20 or more prompts with citations. The table shows the 40 largest, with each market's top review site and that site's share of the market's review-site citations.

Software markets mostly led with G2 or Gartner Peer Insights. Full-Stack Observability Platforms led with Gartner Peer Insights (61.8% of 1,223 review-site citations). Agile Project and Issue Management Software led with G2 (48.1% of 1,051). Consumer markets led with testing and local sites: Online Mattress Shopping and Comparison with RTINGS, Pet Insurance Plans with Consumer Reports, Personal Injury & Accident Lawyers with Avvo. Reddit and Community Marketing Services, a market for agencies, led with Clutch (66.2% of 1,338).

41 markets had 20 or more review-site citations, enough to name a leader. G2 led 16 of them. Gartner Peer Insights led 6, Consumer Reports 4 and PCMag 4. Houzz led 2. Nine sites led one market each: Clutch, Zocdoc, SourceForge, Glassdoor, Avvo, Yelp, RTINGS, Angi and Capterra.

Capterra's one market was Property Management Software & Services, where it had 22 citations against 19 for G2 and 19 for Gartner Peer Insights.

Across the 56 markets with 20 or more prompts, G2 had more citations than Capterra in 36. Capterra had more in 1. Neither was cited in 19, mostly consumer markets.

In the 25 markets with at least 20 G2 and Capterra citations combined, G2 led 24. Capterra came closest in Corporate Learning Management Systems (LMS/LXP), with 68 citations to G2's 99, and in Agile Project and Issue Management Software, with 161 to G2's 506.

28 markets had at least 20 review-site citations on each engine. ChatGPT Search and Google AI Mode had the same top review site in 20 of them, or 71%. The 8 disagreements are below.

Most disagreements follow the engine split above. In Satellite Risk Intelligence Platforms and Field Service Management Software, ChatGPT Search led with G2 and Google AI Mode with Gartner Peer Insights. In Small Business Accounting Software, ChatGPT Search led with Capterra and Google AI Mode with PCMag, which ChatGPT Search did not cite at all.

The first-named brand is the brand an answer mentions first. We matched review-site product pages to the brand they describe and compared the same brand in the same market. When the answer cited the brand's own G2 page, the brand was named first in 37.4% of 880 mentions. When the answer cited no review site, the same brands were named first 20.3% of the time.

The gap was similar for Gartner Peer Insights (40.6% vs 22.6%, 480 mentions) and smaller for Capterra (33.1% vs 23.3%, 290 mentions). When the answer cited a review page about another brand or a category, the brand was named first 19.3% of the time, close to the 20.5% baseline.

This does not show that a review page causes a first mention. An answer that focuses on one brand is more likely to cite that brand's profile. These samples are small: under 1,000 mentions per site.

We sorted each cited review-site URL by its pattern. Category pages (a ranked grid of products in one category) took 31.7% of review-site citations, and best-of lists took 29.9%. Product or business profile pages took 10.9%.

Gartner Peer Insights citations were 79.6% category pages, and GetApp's were 85.5%. G2's largest group was best-of lists (36.2%). Its article site, learn.g2.com, supplied 6,490 of G2's citations. Capterra had the highest product-page share among software sites, 27.9%. Trustpilot was the exception: 93.3% of its citations were company review pages.

On a fixed panel of 9,971 prompts, review sites took between 0.85% and 2.53% of citations in every reported month from October 2025 to September 2026, on both engine lines. The share was 1.27% in November 2025 and 1.92% in September 2026.

Reddit moved more. On the ChatGPT line, Reddit's share was 2.06% in November 2025 and 0.18% in September 2026. In all ChatGPT Search answers, Reddit's weekly share fell from 5.70% in the week of July 13 to 0.41% in the week of August 17, 2026, soon after the switch to gpt-5-6. In September, the ChatGPT line cited review sites about 10 times as often as Reddit (6,376 vs 666 citations). Google AI Mode kept Reddit at 5.46% in the week of September 21.

Six markets with 20 or more prompts had zero review-site citations in 90 days. In both pistol markets, YouTube was the most-cited website, followed by Reddit and pewpewtactical.com. VC & Angel Investor Databases relied on linkedin.com and openvc.app. Prediction Market Betting Platforms cited the platforms themselves, polymarket.com and kalshi.com.

In these markets, a review-site profile would not reach the sources AI uses. The specialist sites and video channels are the review layer.

This is an observed data cut of a Parse mirror over the stated window. A citation is one cited page in one answer; repeated links to the same page in one answer count once. We assigned review sites from a fixed list of 33 by web address. G2 includes learn.g2.com. Gartner Peer Insights includes only gartner.com/reviews pages, not Gartner research. Tech media with review sections, such as TechRadar, CNET and Tom's Guide, are not counted as review sites. Sites with under 30 citations are grouped as other review sites.

Markets are public markets on the Parse index; brand-specific topic sets are excluded. A prompt belongs to one market. Page types come from URL patterns, so a page can be misfiled. The 12-month panel joins two engine generations, so its line shows each engine pair, not one continuous engine. Google AI Mode's citations per answer dropped in late August 2026 for reasons we do not know; shares stay comparable because they divide by the same total. We computed the headline two ways: 4.6 to 1 from page-level classification and 5.0 to 1 from website-level counts.

This study compares citations by market. It does not measure review scores or whether a citation changed a recommendation.

Pick the review site by market and engine, not by habit. In software, G2 was cited 4.6 times as often as Capterra and led 24 of 25 markets where both appeared. Gartner Peer Insights is the first review source for Google AI Mode in enterprise categories. In consumer markets, product-testing sites such as RTINGS and Consumer Reports matter more than user-review platforms, and PCMag only reaches Google AI Mode.

Review your sources each quarter. ChatGPT Search’s mix changed sharply in August, so the review site that matters most today may change.