What Is Share of Voice?
Share of voice (SOV) is a marketing metric that measures a brand's proportion of the total advertising, media, or conversation activity within a defined category or market compared to its competitors. It answers the question: of all the noise in this category, how much of it is about us?
SOV was originally a paid media metric, calculated as a brand's advertising spend divided by total category advertising spend, multiplied by 100. A brand spending $2 million in a category where total advertising spend is $10 million has a 20% SOV in paid media. This definition remains standard in traditional and digital advertising contexts.
The metric has since expanded to cover earned and organic dimensions. Earned share of voice measures a brand's proportion of all media mentions, press coverage, and social conversations in the category. Organic share of voice measures what percentage of non-branded category search results are captured by a brand's content. Each variant measures a different dimension of market presence.
Why Share of Voice Matters for Marketers
Share of voice is the leading indicator of market share. The relationship between SOV and share of market (SOM) is one of the most durable findings in marketing science. Research by Les Binet and Peter Field, analyzing decades of IPA Effectiveness cases, established that brands with SOV above their SOM tend to grow; brands with SOV below their SOM tend to decline. Excess SOV (SOV minus SOM) is the engine of long-term brand growth.
This relationship provides a strategic argument for brand investment that CFOs can understand. If your brand holds 15% market share but 8% share of voice, it is losing ground — competitors talking more loudly in the category will draw awareness and consideration away over time. Investing to close the SOV gap is predictive of future market share gains.
SOV also benchmarks competitive position with real-time sensitivity. A brand can track whether it is gaining or losing voice relative to competitors as competitive activity changes, campaign investment shifts, or PR events occur — allowing faster strategic response than market share data (which is often reported with long lags).
How to Measure Share of Voice
For paid media SOV: calculate brand ad spend as a percentage of total category ad spend. Source competitive spend data from platforms like Nielsen Ad Intel, Kantar Media, Pathmatics, or Semrush's advertising research tools.
For earned/organic SOV: use media monitoring platforms (Brandwatch, Mention, Meltwater) to count total brand mentions across news, social, and web, and divide by total category mentions across the same platforms in the same period.
For organic search SOV: use tools like Semrush or Ahrefs to calculate the percentage of organic search traffic (or keyword visibility scores) your domain captures versus competitors across a defined keyword set representing the category.
Track SOV monthly against a defined competitive set. Establish a baseline, set a SOV target, and report progress quarterly. Correlate SOV movements with brand awareness survey data to validate that increasing SOV is translating to awareness gains.
How to Increase Share of Voice
SOV growth requires either increasing your own presence or reducing competitors' relative presence. The primary lever is investment: more content, more paid media, more PR, more community activity. But efficiency matters too — reaching the right audiences with the right content generates more SOV per dollar than broad, untargeted spending.
Earned media (press coverage, third-party reviews, analyst mentions) generates SOV without proportional spend. Brands with active PR programs generate SOV in excess of their paid media investment. Community-led growth, influencer partnerships, and organic social content all contribute to earned SOV at scale.
Identify SOV gaps by category topic. A brand may have strong overall SOV but low SOV within a specific subtopic or use case. Targeted content and PR investment in the gap areas builds overall share more efficiently than diffuse, category-level investment.
Share of Voice and AI Search
AI search is creating a new dimension of share of voice: AI share of voice, which measures how frequently a brand is cited, mentioned, or recommended in AI-generated answers relative to its competitors. A brand with strong traditional SOV may have poor AI SOV if its content is not structured for AI citation or its public presence is not optimized for the query types AI models respond to. Monitoring AI share of voice — tracking how often a brand appears in AI-generated responses to target category queries — is becoming essential for brands whose buyers use AI platforms as primary research tools.