Share of voice
What is share of voice?
Share of voice (SOV) is the share of the available visibility in your market that your brand captures, compared with competitors. In SEO it is usually your share of estimated clicks across a set of tracked keywords. In AI search it is your share of brand mentions or citations across a set of tracked prompts.
The term comes from advertising, where it meant a brand’s share of total ad spend or ad impressions in a category. Search and AI versions apply the same idea to organic visibility. The key is a fixed denominator: a defined set of keywords or prompts and a defined list of competitors, so the number can be compared over time.
Why share of voice matters for SEO
Share of voice puts your numbers in context. A 30% mention rate in AI answers sounds weak until you see that the market leader has 35% and everyone else is below 10%. Rankings and mention rates alone don’t tell you whether you are winning.
It is also a good executive metric. It moves slowly, it is relative to competitors and it covers a whole topic rather than one keyword.
How to calculate share of voice
- Choose the set: the keywords you track in rank tracking, or the prompts you track in AI visibility.
- Choose the competitors to compare against.
- For search, estimate the clicks each brand gets across the set (search volume × expected CTR at each brand’s position) and divide each brand’s total by the total of all brands.
- For AI answers, count how many answers mention or cite each brand, and divide by the total mentions across all brands.
- Recalculate on the same set each month or quarter.
Share of voice example
You track 50 prompts across 4 assistants (200 answers). Across those answers, brands are named 400 times: you 80, competitor A 140, competitor B 100, others 80. Your AI share of voice is 80 ÷ 400 = 20%; competitor A’s is 35%.
Share of voice FAQ
What is a good share of voice?
It depends on how many competitors share the market. The useful comparison is with your direct competitors and with your own number last quarter.
Is share of voice the same as visibility score?
They are close. A visibility score measures your own estimated share of clicks for a keyword set; share of voice compares that against competitors so the shares add up to 100%.
Related SEO terms
An SEO visibility score is a single number showing how visible a site is in search for a set of keywords, weighting rankings by expected clicks.
Brand mentions are references to your brand name on other websites or in AI answers, with or without a link to your site.
AI visibility is how often and how prominently AI assistants such as ChatGPT, Gemini, Claude and Perplexity mention your brand or cite your site.
Rank tracking is checking where your pages rank in search results for chosen keywords over time, by device and location, to measure SEO progress.
Prompt tracking is running a fixed set of questions through AI assistants on a schedule to track brand mentions, citations and position.