Share of voice in AI search is the percentage of all the names an assistant mentions for a topic that are yours. If an assistant names ten people across the questions in your niche and two of them are you, your share of voice is 20 percent. It is the honest way to measure your standing, because it counts you against the real competition the AI actually surfaces, discovered rather than assumed.
Being named is good, but the question that matters is how you stack up against everyone else the assistant recommends. Share of voice answers exactly that, measured against the people the AI names instead of you.
Tracked over time, it is a robust signal: it smooths the run-to-run variation of AI answers into a trend you can move.
Ask the assistants the real questions in your field, repeatedly, and count every person named. Your share of voice is your mentions over the total. Surfd measures this for a person, alongside your visibility, position, and the sources cited.
Visibility is how often you appear at all. Share of voice is how much of the total attention is yours once you and everyone else are counted. Both matter, and together they tell the fuller story.
Yes, by strengthening the real signals the engines read so you are named more often for the questions that matter, and by understanding what makes the people named instead of you citeable.
Surfd measures how the assistants actually describe you, scores your discoverability, and drafts the fixes. Free to start.