AI share of voice is your brand's mentions divided by the mentions of every brand you track, on the same prompts and the same AI platforms, reported separately for each platform. If you're named 27 times and all tracked brands together are named 100 times in ChatGPT's answers, your ChatGPT share of voice is 27%.

Each part of that sentence hides a choice: which prompts, which competitors, how many runs, and whether you divide by mentions or by answers. Each choice changes the number, and it's why two tools can show the same client two different scores. Below: the calculation, a worked example on three platforms, and how to report the number so it means something to a client.

What AI share of voice means

AI share of voice is your slice of all the brand names AI answers give in your category. It answers a competitive question: when ChatGPT, Gemini, Perplexity or Google's AI Overviews name brands for your buyers' questions, how many of those names are yours?

The idea comes from advertising and PR, where share of voice meant your share of the ad spend or media coverage in a market. In AI answers there's no spend to compare. What you can count is how often each brand gets named in the answers to a fixed set of questions.

Of the numbers in an AI visibility report, it's the one that compares you directly with named competitors. Mention rate (the share of answers that name you) tells you how often you show up. Share of voice tells you how much of the conversation you hold compared with the brands you compete against. Our guide on how to measure AI visibility covers the other metrics, and if you're coming from SEO, our GEO vs SEO guide explains what changes when the result is an answer instead of a ranking.

How to calculate AI share of voice

You calculate AI share of voice in four steps: fix the prompts and competitors, count how many answers name each brand on each platform, divide your count by the total for all tracked brands, then report each platform separately. Tracking AI share of voice in a tool does the counting for you, but it's worth doing once by hand so you know what the number contains.

How to calculate AI share of voice: fix the prompts and competitors, count answers per brand, divide by the total, report per platform