What Is AI Share of Voice?

AI share of voice (SOV) is the percentage of all brand mentions in AI-generated answers that belong to your brand, measured across a fixed set of category prompts. Ask ChatGPT, Perplexity, and Gemini your category's buying questions repeatedly; count every brand named; your share of that total is your AI SOV. It is the direct descendant of the media-planning metric, transplanted from ad impressions to generated answers.

How is it calculated in practice?

AI SOV = (your brand mentions ÷ all brand mentions in tracked answers) × 100

Rigor lives in three choices. The prompt set must reflect real buyer language across funnel stages, not just head terms. Sampling must be repeated — engines answer non-deterministically, so single runs mislead — and multi-engine, because SOV routinely differs 3-5x between ChatGPT and Perplexity for the same brand. And the competitor set must be discovered from the answers themselves: engines regularly surface rivals you were not tracking, which is exactly the signal competitor analysis exists to catch.

Why does the classic metric transfer so well?

Marketing science established that share of voice predicts share of market: brands whose SOV exceeds their current market share tend to grow, a pattern Les Binet's work on share of search extended to organic signals. AI answers are the newest — and arguably most decisive — voice surface, because an assistant's answer often is the shortlist. A brand at 40% AI SOV in "best email marketing tool" prompts is being placed on the shortlist four times out of ten; a brand at 2% effectively does not exist for assistant-first buyers.

What should you segment SOV by?

Aggregate SOV hides the actionable detail. Mature programs, including teams using Menra's visibility tracking, slice it by engine, by prompt intent (informational vs. commercial vs. switching), by persona framing, and by position — first-mentioned carries more weight than trailing mentions. A 20% SOV composed of first-position mentions on commercial prompts is worth far more than 20% scattered across trailing mentions on informational ones.

Example

An e-signature brand holds 31% AI SOV on Perplexity but 6% on ChatGPT. The gap traces to retrieval: Perplexity cites their well-structured comparison pages, while ChatGPT leans on parametric memory dominated by an older incumbent. One metric, segmented, produced the quarter's entire content roadmap.