Share of voice, or SoV, condenses hundreds of ranking positions into a single competitive metric. It is a weighted sum: each keyword's search volume is multiplied by an expected click-through rate at the position the domain holds, then summed across the keyword set.
How it is calculated
SoV = Σ (search_volume × CTR_at_position) for the domain, divided by the same sum computed for all tracked competitors. The formula depends on the CTR curve used, so different tools produce different SoV values for the same keyword set.
Example
A SaaS brand tracking 200 keywords sees its SoV grow from 8% to 14% after publishing a topic cluster, while the top competitor's SoV falls from 22% to 19%.
How SEM Optimiser reports it
SEM Optimiser publishes the CTR curve it uses in the tooltip on every SoV chart and lets you swap in your own curve derived from Search Console data.
Related terms
- Rank Tracking
Rank tracking is the practice of monitoring a website's position in search engine results for a defined set of keywords over time.
- CTR (Click-Through Rate)
Click-through rate is the percentage of impressions that result in a click, calculated as clicks divided by impressions.
- Impressions
An impression is recorded every time a link to your website appears in a user's search results, regardless of whether the user scrolls to see it.
- Organic Traffic
Organic traffic is the volume of visitors that arrive at a website by clicking a non-paid search engine result.