What changed
Ahrefs has changed the volume model behind Brand Radar’s AI visibility reports. Its new “AI adjusted volume” starts with the Google search volume of a prompt’s parent keyword, then applies a platform-specific ratio based on Ahrefs’ aggregated website traffic from that AI platform relative to Google organic traffic. Brand Radar switched its AI visibility reports to this metric in July, affecting reported Volume and Impressions and potentially AI Share of Voice. Users can temporarily compare the old plain-Google-volume calculation, but Ahrefs says that option and the API’s `search_volume_type` choice disappear on August 31, 2026, after which AI adjusted volume becomes the only calculation.
Why it matters
AI-search tools increasingly present numbers that look like conventional search demand even though ChatGPT, Gemini, Perplexity and other platforms do not publish query-volume datasets comparable to Google Keyword Planner or clickstream-derived search tools. Ahrefs is making its modelling assumption explicit and then embedding it into visibility and Share of Voice reporting. Builders, publishers and marketers using Brand Radar therefore need to interpret changes in weighted impressions or AI Share of Voice partly as changes in the measurement model, not automatically as changes in real AI-user demand. The metric is useful for relative prioritisation, but it is not an observed count of prompts or people.
The estimate begins with Google demand
For each tracked AI prompt, Ahrefs identifies a parent keyword and retrieves that keyword’s Google search volume. It then scales that number with a platform-specific adjustment factor. The resulting figure is intended to approximate demand for an equivalent topic on each AI surface rather than reusing the same Google volume unchanged across every chatbot.
The platform ratio comes from referral traffic, not prompt logs
Ahrefs derives its adjustment ratios from aggregated website traffic attributed to individual AI platforms relative to organic traffic from Google. That gives the company an empirical signal about the relative scale of AI-platform traffic, but it is still an indirect bridge from referrals to prompt demand. AI products can differ materially in how often a query produces an external click, so the ratio should not be read as a direct measurement of total platform usage.
The change affects more than the Volume column
Ahrefs’ changelog says AI adjusted volume affects Volume and Impressions across Brand Radar AI visibility reports and may change AI Share of Voice. A site can therefore see historical or comparative metrics move because prompt weights changed even if the underlying set of AI responses or mentions did not. Teams maintaining dashboards should annotate the methodology change rather than treating the series as perfectly continuous.
August 31 removes the old comparison path
Brand Radar currently allows users to switch back to plain Google keyword volume for comparison. Ahrefs’ API likewise exposes `search_volume_type`, with the adjusted calculation already the default. Ahrefs says the parameter will be deprecated on August 31 and all requests will then use AI adjusted volume, making the new methodology the standard across UI and API reporting.
Use the number as a prioritisation weight, not a census
The practical value is relative: a modelled demand weight can help rank prompts, compare topic groups and make Share of Voice less dependent on treating every prompt as equally important. It should not be used as if Ahrefs had access to platform query logs. Decisions that need actual exposure, visits or revenue still require first-party citation/visibility data where available, referral analytics and downstream conversion measurement.