What is share of voice in AI answers?

Share of voice in AI answers is how often the engine names your brand versus the competitors it names instead, across the prompts your buyers actually ask. If ten high-intent prompts surface twenty competitor mentions total and four of them are you, your share of voice is twenty percent. The other eighty percent is going to whoever the AI shortlists in your place.

It is a simple ratio with an uncomfortable implication: every answer is a fixed-size shelf, and the names on it are zero-sum. When ChatGPT recommends three tools, naming a rival is the same event as not naming you.

Why share of voice is the right scoreboard for AEO

A visibility score tells you whether you show up. Share of voice tells you whether you are winning. That distinction matters because answer engines are winner-take-most. If you read what AEO is, you already know the output is one answer, not ten links, and that being named eighth out of ten gets you nothing.

So “are we visible” is the wrong question once you clear the basics. The right question is relative: of all the brand mentions the AI hands out in our category, what fraction are ours? That framing does three useful things.

• It is bounded and comparable. A score that runs zero to one hundred percent reads the same this week as next, and the same for you as for a competitor.
• It names the opponent. You do not just learn you are at thirty percent. You learn who holds the other seventy.
• It maps to revenue. Share of voice on the prompts that precede a purchase is the closest proxy you have for how often you make the consideration set.

How to compute it

The math is a ratio. The discipline is in the inputs.

For a single prompt, capture the real answer and count brand mentions: yours plus every competitor the AI names. Your share is your mention count divided by the total. For a prompt set, sum across all of them:

share of voice = your named mentions / total brand mentions (you + competitors)

Two refinements make the number honest. First, run each prompt across multiple samples on a cadence rather than once, because a single answer is a coin flip, not a trend. Second, weight position if you can. Being named first in a three-brand answer is worth more than being named last, and a flat count hides that.

This is also where AEO and traditional search diverge. A ranking is a position in a list you can see; share of voice is a fraction of an answer you have to reconstruct from what the model actually said. If that distinction is new, AEO vs SEO walks through why the old scoreboard does not transfer.

The pitfalls that quietly break the number

Share of voice is easy to compute and easy to compute wrong. Four traps account for most bad readings.

Thin sampling. One answer per prompt is noise. Engines vary their wording, their shortlist, and their citations from run to run. You need enough samples per prompt, on a regular cadence, before the ratio stabilizes into something you would put in a deck.

Prompt selection. Your share of voice is only as meaningful as the prompts behind it. Pick prompts no buyer would ever type and you will measure a contest nobody is watching. Anchor the set to the questions a real buyer asks an AI before they shortlist a vendor, not the keywords you wish you owned.

Branded versus non-branded. If you ask “tell me about [your brand],” of course the AI names you. That inflates the number and measures nothing. Real share of voice lives in non-branded, category-level prompts where you are competing for the slot, not defending your own name. Track the two separately and never blend them into one figure.

Competitor set drift. The denominator is every brand the AI names, not just the three you decided are your rivals. If the engine keeps surfacing a competitor you are not tracking, your number is wrong until you add them. Let the answers tell you who the field is.

What good looks like

There is no universal target, because share of voice is relative to your category and competitor set. What good looks like is directional and honest.

• A number that holds steady across samples, so you trust it.
• A number that is rising on the prompts tied to revenue, even if it is modest in absolute terms. Going from twelve to twenty percent on your money prompts beats sitting at fifty percent on prompts no buyer asks.
• A clear read on who holds the rest, and at least one prompt where you have a concrete reason to think you can take a point of share back.

Share of voice is not a vanity score. It is a competitive scoreboard for a surface most teams cannot see, and the brands that track it early will be the ones defending the answer while everyone else is still optimizing for the click.

Sonarvue computes this continuously: it captures the real answers across all six engines on your cadence, judges who is named in each, and rolls them into a share-of-voice trend with an alert when a rival moves. But the scoreboard starts the moment you decide to count.