What Is Share of Voice?
Share of voice is a comparison, not a count: it divides one brand's presence by the presence of every brand in a defined category. The term began with advertising spend. Les Binet and Peter Field's 2019 report for the LinkedIn B2B Institute describes it as a brand's “share of voice” “(typically defined as its share of all category advertising expenditure)”. PR and SEO tools now apply the same ratio to coverage, mentions, clicks and AI answers.
No standards body publishes a single definition that every channel uses. The table quotes the definitions we read, verbatim, and labels who wrote each one. Vendor definitions describe how that vendor's product calculates the metric.
| Context | Definition (verbatim) | Source and type |
|---|---|---|
| Advertising | “a brand’s ‘share of voice’ (typically defined as its share of all category advertising expenditure)” | Les Binet and Peter Field, The 5 Principles of Growth in B2B Marketing, LinkedIn B2B Institute, 2019 (research report) |
| Earned media and PR | “the total number of mentions, conversations, or coverage your brand or product receives compared to competitors within a specific market, timeframe, or channel.” | Cision, What is Share of Voice?, November 2025 (vendor) |
| Organic search rankings | “The share of voice (SOV) metric shows the percentage of traffic that your target website gets, compared to the traffic of other websites.” | Ahrefs Help Center, Rank Tracker, updated September 3, 2026 (vendor) |
| AI answers | “This is a brand's percentage share of impressions compared to other tracked brands.” | Ahrefs Help Center, AI Visibility Metrics, Brand Radar, updated September 3, 2026 (vendor) |
| AI answers | Share of Voice “Compares your brand's overall visibility in AI answers against competitors, visualizing the market share of mentions for each brand” | Semrush Knowledge Base, Brand Performance Reports (vendor) |
What the definitions share is the structure: your number on top, the category's total underneath, over one market and one period. What they do not share is the unit. Spend, articles, mentions, estimated clicks and AI-answer impressions produce different percentages for the same brand, so a share of voice figure means little until you know which unit and which competitor set it uses.
The Share of Voice Formula
Share of voice is calculated by dividing a brand's total by the category total and multiplying by 100. Cision gives the earned-media version as “Share of Voice = Brand Mentions ÷ Total Industry Mentions x 100”; the advertising version uses spend in place of mentions. The general form:
Share of voice (%) = (your brand's total ÷ total for all brands in the set) × 100
Excess share of voice (ESOV) = share of voice − share of marketThe ESOV line comes from Binet and Field, who call it “extra” share of voice and define ESOV “as the difference between SOV and SOM” (share of market). This page uses the label “excess share of voice” for the same measure.
Worked example (hypothetical numbers)
The figures below are invented to show the arithmetic. They are not benchmarks. Suppose a company tracks four competitors' articles in trade and national media for one quarter, and also weights each article by the outlet's estimated audience.
| Brand (hypothetical) | Articles in Q3 | Share of voice by articles | Estimated audience (millions) | Share of voice by audience |
|---|---|---|---|---|
| Your company | 30 | 30 ÷ 120 = 25.0% | 4 | 4 ÷ 20 = 20.0% |
| Competitor A | 45 | 37.5% | 10 | 50.0% |
| Competitor B | 30 | 25.0% | 3 | 15.0% |
| Competitor C | 15 | 12.5% | 3 | 15.0% |
| Total | 120 | 100% | 20 | 100% |
The same coverage gives your company 25% by article count and 20% by audience. Neither is wrong; they answer different questions. If this hypothetical company also held a 30% share of market, its ESOV by article count would be 25 − 30 = −5 points. Pick one unit, write it down, and keep it fixed across reporting periods.
How vendors calculate it for search and AI
- Ahrefs Rank Tracker (organic search): “Total clicks your target receives from all Tracked keywords / Total clicks going to all result in the SERP receives for all Tracked keywords”. The clicks are Ahrefs' estimates, and the keyword list is the one you choose to track (Ahrefs).
- Ahrefs Brand Radar (AI answers): impressions are “calculated by summing up search volumes (based on Google) of prompts where your brand appears as an AI Answer”, and AI share of voice is your share of those impressions. Across several platforms it is “a weighted average where platforms with more impressions have more weight” (Ahrefs).
- Semrush Position Tracking (related metric): Semrush's Visibility % is “based on the click-through rate (CTR)” of a site's positions in Google's top 100 for the tracked keywords. It is an absolute visibility score for one site, not a share of a competitor total (Semrush).
Where Share of Voice Comes From: Advertising and ESOV
Share of voice began as an advertising budgeting measure, and its best-known use is comparing it with share of market. Binet and Field write that brands which set share of voice above share of market “tend to grow (all other factors being equal), and those that set SOV below SOM tend to shrink.” They add that this “share of voice rule has been known for 50 years”.
Their 2019 report, which analysed the UK IPA (Institute of Practitioners in Advertising) Databank of campaigns entered for the IPA Effectiveness Awards, gives one quantified finding: “For consumer brands, 10% extra share of voice causes market share to rise by 0.6 % points per annum, all else being equal. For B2B, the corresponding figure is 0.7%.” The same report sets out the limits plainly. B2B sample sizes are “small, at less than 50 cases”, the Databank “is biased towards effective campaigns”, and the authors “stress that these results are tentative”.
Rise in market share, percentage points per year, for 10% extra share of voice (ESOV), advertising spend; IPA Databank analysis, 2019
Source: Les Binet and Peter Field, The 5 Principles of Growth in B2B Marketing, LinkedIn B2B Institute, 2019.
Measured on advertising spend, not on earned coverage or AI answers. The authors call the B2B result tentative, based on fewer than 50 cases from a databank biased towards effective campaigns.
Two things follow for anyone using the metric outside advertising. First, the published relationship was measured on advertising spend, not on press mentions, organic clicks or AI answers; we found no primary source that tests the same rule for earned coverage. Second, it is a relationship between share of voice and share of market, so a share of voice figure on its own says little about growth. This page does not cite a “good” share of voice benchmark because none of the primary sources we read publishes one.
Types of Share of Voice
Share of voice is calculated separately for each channel, because each channel has its own unit and data source. Cision lists traditional media coverage, social media conversations, paid advertising and search engine results as contexts where the metric applies. Tool vendors have added AI answers. The table sets out what each variant counts.
| Variant | What is counted | Where the data usually comes from | Main limitation |
|---|---|---|---|
| Advertising (paid media) | Ad spend, or impressions or ratings bought, as a share of the category | Ad-spend estimates; in paid search, Google Ads impression share is the closest platform metric | Competitors' spend is estimated, not reported |
| Earned media (PR) | Articles, broadcast items or podcast mentions naming each brand | Media monitoring tools or a manual coverage log | Counts depend on the tool's source list and on how brand names are matched |
| Social | Posts or mentions naming each brand | Social listening tools | Platform access varies; bots and spam inflate counts |
| Organic search | Estimated clicks or visibility across a chosen keyword list | SEO rank trackers (Ahrefs, Semrush) | The result depends on the keywords you choose to track |
| AI answers | Brand mentions, or volume-weighted impressions, in AI assistant responses to a prompt set | Ahrefs Brand Radar, Semrush AI reports, or a manual prompt log | Answers vary between runs; the prompt set drives the result |
Share of Voice in AI Answers
AI share of voice measures how often assistants such as ChatGPT, Perplexity, Gemini or Google AI Mode name your brand compared with named competitors. Semrush's Brand Performance reports cover “ChatGPT, Google AI Mode, Perplexity, and Gemini” and show share of voice alongside sentiment. Ahrefs Brand Radar bases it on mentions weighted by the search volume of each prompt.
The two vendors count differently. Ahrefs counts a mention once per response: an answer that names Salesforce three times “is still only counted as 1 mention”. It then weights by impressions. Semrush describes its share of voice as “the market share of mentions for each brand”, and lets you compare up to 9 competitors. Ahrefs adds a warning that applies to every AI share of voice figure: “AI Share of voice is a comparative metric, and can change a lot depending on how you've set up the entities for you brand and competitor brands.”
A free version works on the same principle. Write a fixed list of category prompts (for example “best [category] software for [use case]”), run each on each assistant on a set date, and record every brand named. Your share of voice is your mentions divided by all brand mentions. Our guide on how to check what ChatGPT, Perplexity and Gemini say about your company sets out a repeatable prompt audit you can reuse for this count. Because AI answers change between runs, compare like with like: same prompts, same assistants, same week of the month.
What Share of Voice Is Not
Share of voice measures volume relative to competitors. It does not measure tone, quality or business results, and treating it as any of those is the most common reporting error. Cision's own guide to the metric puts it this way: “In isolation, however, it can’t tell you about the quality of coverage.”
- Not sentiment. A product recall can push a brand's share of voice up. Semrush's Brand Performance report plots share of voice against sentiment so that brands “with high visibility but poor sentiment” stand out.
- Not share of market. Share of market is your share of category sales. The advertising research compares the two; it does not treat them as the same thing.
- Not Google Ads impression share. Google defines impression share as “impressions / total eligible impressions”, where eligible impressions are estimated for your own ads. The denominator is your opportunity, not the category total (Google Ads Help).
- Not reach or audience. Ten mentions in small newsletters and ten in national outlets give the same count-based share of voice.
- Not advertising value equivalence (AVE). AVE prices coverage as if it were advertising. AMEC's glossary calls AVE “a discredited approach to gauging the value of public relations” (AMEC). Share of voice is a ratio and puts no dollar value on coverage.
Share of Voice vs Related Terms
Share of voice is often reported next to metrics that sound similar but use a different denominator or measure something else. The table shows how each one is calculated or defined, and by whom.
| Term | What it measures | Defined or documented by | How it differs from share of voice |
|---|---|---|---|
| Share of voice (SOV) | Your share of category spend, coverage, mentions, clicks or AI answers | Binet & Field (advertising); vendors per channel | — |
| Share of market (SOM) | Your share of category sales | Binet & Field use it as the comparison point | Measures sales, not visibility |
| Excess share of voice (ESOV) | SOV minus SOM | Binet & Field, 2019 | Derived from SOV; the measure the growth research uses |
| Impression share | Your ad impressions ÷ impressions you were eligible for | Google Ads Help | Denominator is your own estimated opportunity |
| Visibility % (Semrush) | CTR-weighted visibility for tracked keywords | Semrush KB | An absolute score for one site, not a share |
| Sentiment | Tone of mentions (favourable, neutral, unfavourable) | Monitoring and AI-visibility vendors | Measures tone, not volume |
| AVE | Coverage priced as advertising | AMEC calls it “discredited” | A money figure, not a ratio |
How to Measure Share of Voice for Your Company
A share of voice figure is only useful if the competitor set, channel, unit and period stay the same from one report to the next. The steps below are a practical method, not a standard; no body we found publishes one for earned media.
- Define the competitor set. List the 3–8 brands a buyer would actually compare you with. Adding or dropping a brand changes every percentage.
- Pick one channel and one unit per figure. For example, “articles in trade and national media”, or “brand mentions across 40 AI prompts on four assistants”. Report channels separately rather than adding them together.
- Fix the period. Monthly or quarterly. Compare the same period year on year to smooth out launches and news cycles.
- Collect the counts with one tool. Free alerts work at small scale; our guide to monitoring brand mentions with Google Alerts and free tools covers set-up, and Google Alerts vs Talkwalker Alerts compares their coverage. Paid platforms report share of voice directly; our Meltwater vs Muck Rack and Muck Rack vs Cision comparisons cover what each includes. Do not mix tools in one calculation, because each has its own source list.
- Apply the formula and record the method. Note the tool, query, date range and any exclusions (press-release copies, job ads, unrelated namesakes) next to the number.
- Pair it with a quality measure. Add sentiment, outlet tier or key-message pull-through, and tie it to outcomes where you can. Our guide to measuring whether a placement worked covers what to track beyond counts.
Common Misconceptions About Share of Voice
Most share of voice mistakes come from comparing figures built on different units, or from reading a volume metric as a quality or growth metric. Each row checks a common claim against a source.
| Myth | What the source actually says | Source |
|---|---|---|
| “A higher share of voice means better coverage.” | Share of voice “can’t tell you about the quality of coverage” in isolation. | Cision |
| “There is a standard good share of voice, such as 20%.” | The advertising research compares SOV with share of market (ESOV); it does not set a fixed target. We found no primary source publishing a universal benchmark. | Binet & Field, 2019 |
| “Share of voice in PR is proven to grow market share.” | The published relationship uses advertising spend, and the B2B results are described as “tentative” with fewer than 50 cases. | Binet & Field, 2019 |
| “Impression share is my paid-search share of voice.” | Impression share = “impressions / total eligible impressions”, an estimate of your own opportunity, not the category total. | Google Ads Help |
| “AI share of voice is a stable, objective number.” | It “can change a lot depending on how you've set up the entities for you brand and competitor brands.” | Ahrefs Help Center |
| “Share of voice figures from two tools can be compared.” | Each tool counts its own sources and units: Ahrefs uses estimated clicks for search and volume-weighted impressions for AI; Semrush describes share of mentions. | Ahrefs, Semrush |
Frequently Asked Questions
What does share of voice mean in PR?
In PR it usually means your brand's share of all media coverage or mentions in a defined set of competitors, channels and dates. Cision defines it as the mentions, conversations or coverage your brand receives “compared to competitors within a specific market, timeframe, or channel.”
How do you calculate share of voice?
Divide your brand's count by the total count for every brand in the category, then multiply by 100. The count can be ad spend, articles, mentions, estimated clicks or AI-answer impressions, but it must be the same unit for every brand, period and channel.
What is a good share of voice?
There is no universal figure. Share of voice is relative to the competitor set you choose, so 20% can be high in a crowded category and low in a two-brand one. The advertising research by Les Binet and Peter Field compares share of voice with share of market rather than with a fixed target.
What is excess share of voice (ESOV)?
ESOV is share of voice minus share of market. Binet and Field's 2019 report for the LinkedIn B2B Institute says brands that set share of voice above share of market “tend to grow”, and that the rate is proportional to ESOV. They call their B2B findings tentative.
Is share of voice the same as Google Ads impression share?
No. Impression share divides your ad impressions by the impressions you were eligible to receive, so it compares you with your own potential, not with competitors' totals. It is a useful paid-search input, but the denominator differs from category share of voice.
Does share of voice include sentiment?
No. Share of voice counts volume. A brand in a crisis can have a high share of voice from negative coverage. Pair it with sentiment, outlet quality and message pull-through, as Cision's own guidance on the metric recommends.
How do you measure share of voice in AI answers?
Run a fixed set of prompts on each assistant, record which brands each answer mentions, and divide your mentions by all brand mentions. Ahrefs Brand Radar and Semrush's AI reports calculate versions of this; Ahrefs warns its AI share of voice can change a lot depending on how brands are set up.
Can I measure share of voice for free?
For earned media and AI answers, yes, at small scale: log coverage from Google Alerts or Talkwalker Alerts and a fixed prompt set in a spreadsheet, then apply the formula. Paid-tool numbers are more complete but are each vendor's estimate, so do not mix tools inside one calculation.
Sources and Methodology
This explainer was built on October 8, 2026 from the sources below, all read that day. Definitions and formulas are quoted verbatim. The ESOV figures are quoted from the Binet and Field report with its own caveats; we did not reanalyse its data. Vendor help pages describe how each vendor's product calculates share of voice; we did not test any tool or calculate share of voice for any real brand, and the worked example uses invented numbers. Wikipedia's share of voice article was used only as a lead to find sources. We could not reach the Institute for Public Relations' measurement dictionary on the day (the server timed out), so its definition is not quoted.
- research Les Binet and Peter Field, The 5 Principles of Growth in B2B Marketing: Empirical Observations on B2B Effectiveness, LinkedIn B2B Institute, 2019 (PDF dated October 2019; analysis of the IPA Databank). Read October 8, 2026.
- official Google Ads Help, About impression share and Get impression share data. Read October 8, 2026.
- vendor Cision, What is Share of Voice? How to Measure & Increase Brand SoV, published November 18, 2025. Read October 8, 2026.
- vendor Ahrefs Help Center, What is Share of Voice (SoV) and how is it calculated?, updated September 3, 2026. Read October 8, 2026.
- vendor Ahrefs Help Center, AI Visibility Metrics, updated September 3, 2026. Read October 8, 2026.
- vendor Semrush Knowledge Base, Brand Performance Reports. Read October 8, 2026.
- vendor Semrush Knowledge Base, What is Visibility?. Read October 8, 2026.
- trade body AMEC, Glossary – Plain Speaking (entry for AVE). Read October 8, 2026.