Index No. 02 · Haircare · United States · October 2026
We asked five AI engines 49 real haircare questions, three times each, and counted who they named. No consensus pick, a salon tier that owns the shelf, and an independent tier that is finally in the room.
By Vivian Qu · Published 5 October 2026
Findings
1
Olaplex is the most-named brand, in 30% of all answers, but it is named first in only 8%. In sunscreen, one brand was every engine's first pick; here the five engines split three ways. Claude, Perplexity and Grok put Olaplex first most often, ChatGPT puts L'Oréal Paris first, Gemini puts Ouai. The best first-pick rate in the category is 8%, against 20% for EltaMD a month ago. There is a shelf, and nobody owns it.
2
Mass 22%, independent and prestige-indie 21%, dermatologist and scientific 7%, Korean and Japanese 4%. Olaplex, Redken, K18, Kérastase, Living Proof, Pureology and Oribe are all in the top ten. The engines learned haircare from the salon, and they recommend the way a stylist does: by treatment line, not by price.
3
21% of mentions, against 6% in sunscreen. Ouai is named in 20% of answers, Briogeo 13%, Nécessaire 9%, Mielle 6%. But the tier is four names deep. Dae, Crown Affair, Act+Acre, Ceremonia and Gisou are each under 2%. Prose, a brand built on personalisation, was not named once in 735 answers.
4
Named in 26% of answers, ChatGPT's most frequent first pick, the only mass brand in the top ten. It is also the only brand whose own websites are among the twenty most-cited sources: lorealparisusa.com in 104 answers and hair.com, which L'Oréal owns, in 98. Every other brand is learned from magazines. This one is learned from itself.
5
Asked the same question three times, ChatGPT names the same brand first on 19% of prompts (41% in sunscreen). Gemini 22%, Grok 36%, Claude 42%, Perplexity 65%. Haircare answers are lists, a median of seven brands on ChatGPT, Gemini and Grok. In a seven-brand answer, being on the list is the measurement that holds; being first is weather.
6
44% of hair-loss answers name no brand at all, and the ones that do name Nizoral, Rogaine and Nutrafol. On scalp questions the shelf is Neutrogena T/Gel, Nizoral, Head & Shoulders and CeraVe, with the American Academy of Dermatology and PubMed as sources. The derm zone exists in haircare too; it is just narrower than in sunscreen.
The map
Two numbers per brand: how often it is named at all, and, when it is named, how often it comes first. Top right is where a brand wants to be. In this category, nobody is there.
Mention rate against first-pick conversion, top 30 brands
Mention rate is the share of 735 answers naming the brand. Conversion is the share of those mentions where the brand was named before any other. Hover a point for its numbers.
The full data
The findings above are public. The working data is for brand and marketing teams, and we ask for a company email to send it.
Method
Questions
Olaplex is named most often, in 30% of 735 answers from ChatGPT, Claude, Gemini, Perplexity and Grok, but it is named first in only 8%. Unlike sunscreen, where EltaMD was every engine's first pick, no haircare brand is the first pick on all five engines: ChatGPT most often names L'Oréal Paris first, Gemini names Ouai, and Claude, Perplexity and Grok name Olaplex.
They share a shelf but not a favourite. Olaplex, Redken, K18, L'Oréal Paris, Ouai and Kérastase appear across all five, yet each engine puts a different brand first most often. Gemini names the most brands per answer and leans on Redken and Pureology; Perplexity names the fewest; ChatGPT leans on drugstore brands more than the others.
Less often than for sunscreen. Asked the same question three times, ChatGPT named the same brand first on 19% of prompts, Gemini 22%, Grok 36%, Claude 42% and Perplexity 65%. Haircare answers are long lists, a median of seven brands on ChatGPT, Gemini and Grok, so the first slot moves between runs.
Far more than in sunscreen. Independent and prestige-indie brands received 21% of all brand mentions, against 6% in the sunscreen edition. Ouai was named in 20% of answers, Briogeo 13%, Nécessaire 9% and Mielle 6%. Below those four the tier thins quickly: Dae, Crown Affair, Act+Acre, Ceremonia and Gisou were each named in under 2% of answers, and Prose was not named at all.
49 English shopping prompts, none naming a brand, each run three times on ChatGPT, Claude, Gemini, Perplexity and Grok through their APIs on 4 October 2026, with web search on where supported. Every answer was matched against a list of 183 brands and product lines. The full method is published on this page.
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