Sources and comparison notes

A rank-based composite

The revised document explicitly asks each AI to rank five shampoos available in the UK. We preserve those rankings and give each response equal weight. First place earns 5 points, second 4, third 3, fourth 2 and fifth 1. A product absent from an AI’s primary five scores zero. The maximum is 20.

Scalp Advanced scores 5 + 4 + 4 + 5 = 18/20. OUAI Detox scores 0 + 5 + 2 + 4 = 11/20. MONDAY Clarify scores 7/20. Vichy Dercos scores 5/20. Lush Squeak scores 4/20. The order is ChatGPT, Gemini, Claude, Grok.

How ties and alternatives work

Products are ranked by total points. Equal totals are resolved by: (1) most primary top-five appearances; (2) best individual rank; (3) market-share-weighted rank points. The final tie-break is the sum of each AI’s rank points multiplied by its chatbot website-traffic share. Market share does not change the main score. If all these measures are identical, products share a rank; alphabetical order is never a ranking criterion.

Claude’s fifth-place product is Elvive Extraordinary Clay; MONDAY is an alternative in the same paragraph and receives no Claude points. Grok’s fifth-place primary product is Redken Amino-Mint; Living Proof Clarifying Detox is an alternative and receives no points. Vichy’s unranked mentions in ChatGPT and Grok also score zero. Unranked alternatives are excluded from the comparison.

Source responses

This edition uses only the revised “Shampoo for greasy hair(1).docx”. The earlier answers and mention-count composite are superseded. The new question is “Rank the top 5 shampoos for greasy hair available in the UK”. Exact model versions, collection dates and settings were not supplied. The editorial update date is 31 October 2026.

Identity and comparability

Clear abbreviations of Scalp Advanced Anti-Oiliness are treated as the same product. Davines Rebalancing and Davines Naturaltech Rebalancing are normalised to one product. Different shampoos from the same brand remain separate.

What the ranking does not establish

These are four AI answers, not four independent trials. Several refer to the same reviews, especially The Independent. We do not independently endorse their claims about panel scores, stock, prices, clinical efficacy or suitability. The composite measures the supplied preferences and is not a laboratory performance score.

Claims that washing causes rebound oil production, that shampoos regulate oil production, or that they guarantee an extra day between washes are not adopted as proven conclusions. Grok’s “carbonic acid” description of Scalp Advanced is not supported by the manufacturer ingredient list checked for this project. The original wording is preserved on the response pages, with these limitations stated here.

UK prices are listed single-purchase prices retrieved from the linked retailer or manufacturer listings on 31 October 2026, including any displayed promotions. Search listings can lag live prices. Delivery is excluded; check the retailer for current price and availability. These are not claims of the lowest price. Extraordinary Clay was rechecked on 1 November 2026: Luxplus lists a normal non-member price of £4.95 for 400ml but marks it sold out. Superdrug, East End Cosmetics and Approved Food also showed no online stock. The displayed price is a listed price, not a current purchasable offer. Packaging photographs may show a different size from the priced pack. Luxplus price and availability.

How the UK advice was derived

The UK routine summary is drawn from the supplied UK answers: Scalp Advanced across all four lists; MONDAY’s budget positioning in ChatGPT and Grok; OUAI in Gemini, Claude and Grok plus Bumble and bumble in Claude; Hydra Pure in Gemini and Bain Divalent in Grok; Vichy in Claude and Philip Kingsley in Gemini. The original answers are linked below. Unsupported rebound-oil and guaranteed wash-frequency claims are not adopted. Product directions take precedence over conflicting AI usage suggestions.

Source checks retained from this project

These references support general care guidance and selected product checks. They are separate from the incomplete references in the AI responses and do not verify every claim in the revised document.

1. L’Oréal Paris · Hydra Pure range ↗

   Confirms the oily-scalp / dehydrated-lengths positioning and salicylic and hyaluronic acids.

2. L’Oréal Professionnel · Scalp Advanced ↗

   Confirms the anti-oiliness product and 3% AHA formulation. The brand’s sebum-reduction result is for shampoo plus clay, not shampoo alone.

3. OUAI UK · Detox Shampoo ↗

   Confirms the clarifying product, intended use and fragranced formula.

4. American Academy of Dermatology · Healthy hair tips ↗

   Supports washing according to oiliness, scalp-focused shampooing and conditioning according to hair type.

5. NHS · Dandruff ↗

   Supports choosing an anti-dandruff shampoo and consulting a pharmacist; persistent or severe symptoms need assessment.

6. OUAI · Detox usage guidance ↗

   The brand suggests replacing regular shampoo with Detox once or twice a week.

Product image credits

Images are for product identification and come from the linked manufacturer and retailer pages. Packaging and sizes may vary by market and date. Image rights remain with their owners; inclusion does not assert a reuse licence or endorsement.

• Being Nourish + Shine Daily Clean
• Bumble and bumble Sunday Shampoo
• L’Oréal Elvive Extraordinary Clay
• Davines Naturaltech Rebalancing
• L’Oréal Elvive Hydra Pure 72H
• Kérastase Spécifique Bain Divalent
• Living Proof Clarifying Detox
• Lush Squeak
• MONDAY Haircare Clarify
• OUAI Detox Shampoo
• Philip Kingsley Flaky/Itchy Scalp
• Redken Amino-Mint Scalp Shampoo
• L’Oréal Professionnel Scalp Advanced Anti-Oiliness
• Vichy Dercos Anti-Dandruff — Normal to Oily Hair