Share of search is the percentage of all brand searches in a category that are for your brand. If people search for five competing brands a combined 100,000 times a month and 20,000 of those searches are for you, your share of search is 20%.
For a business, share of search is a fast, inexpensive read on brand demand. Research presented through the IPA, the UK's Institute of Practitioners in Advertising, found that it tracks closely with market share and can move before market share does. That makes it a useful early signal for marketing teams that can't wait for quarterly sales data.
What is share of search?
The metric was presented by effectiveness researcher Les Binet at the IPA's EffWorks Global conference in October 2020. According to the IPA's summary, share of search uses organic Google searches, not paid search ads, and is calculated as a brand's searches divided by the total searches for all brands in its category. The data comes from Google Trends, which is free and goes back to 2004.
It's built on branded search: people typing a brand's name because they already know it and are considering it. That's why it works as a measure of brand demand rather than general interest in a topic.
Why share of search matters
It tracks market share. Binet's original analysis covered cars, energy and mobile phone handsets, and found that share of search correlated with market share in all three. A follow-up from the IPA's share of search think tank, published in October 2021, looked at 30 case studies across 12 categories in seven countries. It found that share of search averaged about 83% of a brand's share of market, though the ratio varied by category and country.
It can be a leading indicator. The IPA's 2020 summary says rises and falls in share of search tend to come before similar moves in market share, by up to a year in the car category.
It's cheap and fast. Brand tracking surveys can be expensive and slow. Share of search can be checked weekly using free data.
It connects to advertising. The 2021 findings say brands that spend above their market share and grow their share of voice tend to see share of search rise. Mass-reach media appeared to have more effect than narrowly targeted campaigns.
How share of search works
Define your competitor set
List the brands buyers actually compare you with. The result depends heavily on this list, so keep it consistent over time.
Collect branded search data
Google Trends is the most common source. Keyword tools that estimate search volume can also be used, as long as you stick with one source.
Calculate and smooth
Divide each brand's searches by the total for the whole set. The IPA's 2021 findings recommend a rolling average of 6 to 12 months to smooth out short-term noise.
Know the data's limits
Google's Trends FAQ says the tool uses a sample of searches, normalizes each data point against total searches for that time and place, and scales results from 0 to 100. It also adds small random fluctuations and only shows data for popular terms. Google says Trends data "should always be considered as one data point among others before drawing conclusions."
How to measure share of search
- Pick a market. Choose one country and language at a time, since search behavior differs by region.
- Choose clean brand terms. Use the brand names people actually type. Watch for names that are also common words or shared with unrelated businesses.
- Compare brands in one query. In Google Trends, compare brands side by side in the same search so they're scaled together.
- Export and calculate. Download the data and calculate each brand's share of the total for each week or month.
- Smooth the trend. Apply a rolling average so one news story or campaign doesn't dominate the picture.
- Track it alongside sales. Over time, compare your share of search with your own market share or sales data to see how closely they move in your category.
Common mistakes and misconceptions
"Share of search causes market share." The IPA think tank was clear that its findings show correlations, not causal relationships.
"83% applies to every brand." That figure is an average across the think tank's case studies. The ratio varies by category and country.
"It's the same as SEO visibility." Some SEO tools use similar names for your share of non-branded rankings. Share of search, as defined by Binet and the IPA, is about branded demand.
"Weekly swings mean something." Short-term spikes often come from news, promotions or data noise. Look at the rolling trend.
"It covers all brand demand." It measures Google searches only. People increasingly ask AI assistants for brand recommendations, and those conversations don't show up in search data.
Share of search vs. AI share of voice
Share of search measures how often people look for your brand by name. AI share of voice measures how often AI assistants mention or cite your brand when answering questions in your category. The first shows demand that already exists. The second shows whether AI tools are putting your brand in front of people who haven't decided yet. Tracking both gives a fuller view of brand visibility than either one alone.
How Butter approaches share of search
We don't sell share of search as a separate report. We treat branded search as one of the most useful, if imperfect, indicators of whether a brand is gaining attention. It sits at the intersection of SEO, PR and AI visibility, so we avoid crediting it to any single channel.
Butter Analytics connects website performance across 85+ tools in one dashboard, which makes it easier to view branded and non-branded trends alongside campaigns, PR coverage and other channels. Our GEO plans, starting at $399/month, add monthly AI prompt testing, so you can watch AI mentions and branded demand side by side rather than guessing.
Frequently asked questions
How do you calculate share of search?
Divide the number of searches for your brand by the total searches for all brands in your competitor set, then multiply by 100. The IPA recommends smoothing the result with a 6 to 12 month rolling average.
Who created share of search?
Les Binet presented the metric at the IPA's EffWorks Global conference in October 2020. The IPA later formed a share of search think tank, which published further findings in 2021.
Does share of search predict market share?
Research presented by the IPA found that share of search correlates with market share and that changes in it tend to come before changes in market share. The findings are correlations, and the relationship varies by category.
Where can I get share of search data?
Google Trends is the most common free source. Keyword research tools that estimate branded search volume also work. Whichever you use, keep the source and competitor set consistent over time.