On March 20, 2025, Anthropic released Web Search for Claude.ai, transforming it from a static LLM into an Answer Engine just like ChatGPT with Bing, Perplexity, or Google's AI Overviews.

However, the critical insight is now clear: Claude leverages Brave Search as its primary search backend, confirmed by a statistically significant overlap of 86.7% (13 out of 15 total results) between Claude's cited results and Brave Browser's top non-sponsored results.

How Claude Web Search Actually Works

Claude does not independently crawl the web or retrieve real-time page data directly. Instead, it seems that Claude relies on Brave Search's indexed and cached results. When a query requires fresh content, Claude explicitly conducts a search, shows the search term, and lists underlying results before writing its conversational answer. Citations with direct source links appear inline, similar to ChatGPT.

Search Result Alignment with Brave

I ran a detailed analysis of specific queries which revealed remarkably high alignment:

  • "best men's running shoes 2025" query matched exactly (100%) in the top 5 results.
  • "best dog food brands for natural diet" query matched exactly (100%) in the top 5 results.
  • "best CRM software 2025 top rated comparison" query matched 60% (3 of 5 results), showing minor differences likely due to personalization or algorithmic nuances.

Statistical analysis confirms the observed overlap is far beyond random coincidence (p-value < 0.0001), suggesting Claude directly utilizes Brave's top-ranked organic results without significant re-ranking.

By contrast, ChatGPT, despite using Bing as its backend, shows a much lower alignment of only 26.7% with Bing's top-ranked results. Here's the deal: while you can simply optimize for Claude visibility by targeting Brave, you can't do the same for ChatGPT.

Claude vs ChatGPT

When comparing Claude directly against ChatGPT (powered primarily by Bing), a significant divergence emerges:

  • "best men's running shoes 2025": Only 20% overlap with ChatGPT results.
  • "best dog food brands for natural diet": 40% overlap with ChatGPT results.
  • "best CRM software 2025 top rated comparison": 0% overlap with ChatGPT results.

Overall, Claude's search results show just 20% overlap with ChatGPT, underscoring substantial differences between Brave-based Claude and Bing-based ChatGPT.

Brand Implications

Given Claude's strong alignment with Brave Search's organic rankings, traditional SEO focused on Brave Search becomes the most effective strategy for achieving Claude visibility. Unlike ChatGPT, which shows divergence from its supposed backend, Claude directly reflects Brave's ranking signals:

  • Claude offers no publisher-specific opt-out; publishers must rely solely on standard web indexing controls (noindex tags and robots.txt as interpreted by Brave).
  • Publishers cannot directly block or manage Claude's summarization through dedicated Claude-specific tags, limiting their direct control over content usage.

How to Get Ranked in Claude Web Search

To enhance visibility in Claude's search ecosystem:

  1. Traditional SEO practices targeting Brave Search rankings are crucial for Claude visibility.
  2. Provide clear, concise, structured answers directly addressing user queries.
  3. Leverage structured data markup (FAQ, Article, How-To) for optimal snippet extraction.
  4. Implement llms.txt (Anthropic being an early adopter) to explicitly define content usage permissions.
  5. Ensure your content is crawlable and indexable by Brave's crawler, strictly adhering to Googlebot indexing rules.

Ultimately, publishers targeting Claude Web Search must strategically optimize for Brave Search rankings, as Claude transparently mirrors Brave's organic results, distinctively contrasting with ChatGPT's more complex relationship with Bing.

if you are interested in improving how your brand shows up in AI Search.