Share of voice (SOV) is the percentage of a market's visibility or conversation that belongs to your brand compared with its competitors, measured in a specific channel: advertising, search, social media or AI answers.
It is a comparative metric. Traffic up 10% means little if your competitors grew 30%. Share of voice puts your results in context, which is why it shows up in benchmarking reports and among brand-level marketing KPIs.
Share of voice formula
SOV = your brand's presence / total market presence × 100
Example: the five leading brands in your category get 2,000 mentions in a month. Your brand accounts for 300. Your share of voice is 300 / 2,000 × 100 = 15%.
You choose the denominator: which competitors, which keywords, which questions. Change the set and the percentage moves even though nothing happened in the market. So fix it, document it and leave it alone between measurements.
Types of share of voice
Advertising share of voice
The original concept: your share of the category's ad spend (or impressions). If your category spends €100,000 a month on media and you spend €20,000, your advertising SOV is 20%. In Google Ads, the Auction insights report shows your impression share alongside that of competitors bidding on the same searches, which is a good proxy on the Search Network.
SEO share of voice
It measures how much of the available organic clicks for a keyword set each domain captures. For each keyword, multiply search volume by the estimated CTR of each domain's position, then add it all up. Using a CTR curve assumed for this example (position 1: 30%, position 2: 15%, position 3: 10%):
| Keyword | Volume | Your site | Competitor A | Competitor B |
|---|---|---|---|---|
| Keyword 1 | 1,000 | Position 1: 300 clicks | Position 2: 150 clicks | Position 3: 100 clicks |
| Keyword 2 | 2,000 | Position 3: 200 clicks | Position 1: 600 clicks | Position 2: 300 clicks |
| Total | 500 clicks | 750 clicks | 400 clicks |
The estimated total is 1,650 clicks. Your SEO share of voice is 500 / 1,650 × 100 = 30.3%. Every tool uses its own CTR curve, so only compare figures calculated with the same method.
Social share of voice
Your mentions on social media, forums and news sites out of all mentions in your category. Social listening tools count them, and many let you separate positive from negative mentions, because dominating the conversation with a campaign is not the same as dominating it with a crisis.
AI share of voice
Your share of the brand mentions in AI search answers for a set of buyer questions. Example: you run 50 questions across three engines and count 400 mentions between your brand and three competitors; if 80 are yours, your AI share of voice is 20%. This is not the same as mention rate (the share of answers you appear in): you can show up in many answers and still hold a small share if your competitors appear in all of them. We cover this in our entry on GEO. The AI visibility checker shows your share of mentions against up to three competitors.
Share of voice vs market share
How share of voice relates to market share (share of market) is the most useful part of the metric. The gap between the two is called excess share of voice (ESOV):
ESOV = share of voice − market share
John Philip Jones set out the idea in the early 1990s, and Les Binet and Peter Field later revisited it in their analyses of campaigns for the IPA (the UK's Institute of Practitioners in Advertising). The conclusion, in qualitative terms: brands whose share of voice exceeds their market share tend to grow over time, while those below it tend to lose share. It is a pattern observed across many brands, mainly for advertising spend and over the long term, not a guarantee for every case.
How to measure each type
| Type | What you count | Where the data comes from |
|---|---|---|
| Advertising | Spend or impressions | Auction insights, ad intelligence tools |
| SEO | Estimated clicks over a fixed keyword set | A rank tracker that follows competitors |
| Social | Brand mentions | Social listening tools |
| AI | Mentions in answers to buyer questions | Questions run repeatedly across several AI engines |
How to use share of voice in decisions
- Compare it with your market share. If your SOV sits below it, that is a sign your investment in visibility is not enough to sustain sales.
- Break it down. A 25% overall figure can hide 40% on informational keywords and 5% on transactional ones. Splitting by topic, channel or AI engine tells you where to invest.
- Watch the trend, not the single reading. One month says little; the quarterly trend tells you whether you are gaining or losing ground.
- Put it on a dashboard next to business metrics (leads, sales, ROI) so you do not optimise visibility that does not sell.
Common mistakes
- Changing the competitor or keyword set between measurements and comparing the results.
- Comparing SOV from two different tools that use different methods.
- Counting mention volume without checking whether mentions are positive or negative.
- Measuring AI share of voice with a single question or a single run.
Frequently Asked Questions
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It is your brand's share of visibility against its competitors in a channel: advertising, search, social media or AI answers. It is expressed as a percentage and answers a simple question: of all the conversation in your market, how much of it is yours?
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Divide your brand's presence by the total presence of the market you are measuring and multiply by 100. If the five brands in your category get 2,000 mentions in a month and 300 are yours, your share of voice is 15%. Presence can be spend, impressions, estimated clicks or mentions, depending on the channel.
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There is no universal number: it depends on how many competitors you include and on the channel. The most useful benchmark is your own market share. If your share of voice is above it, you have room to grow; if it is below, you risk losing ground. The trend matters too: you want it rising quarter on quarter.
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Share of voice measures visibility (how much you are seen or talked about) and market share measures sales (how much of the category's business is yours). The gap between the two is called excess share of voice and is one of the most widely used indicators of whether a brand is likely to grow or lose share.