Dimension 2 of 12
Market size and traffic share analysis
Updated
What is market competitor research?
Market analysis for competitor research sizes the whole category and shows how attention is split: market size, total traffic across competitor sites, how many sites compete, each rival's share of that traffic and the split by channel (direct, referral, search, social and paid). SEMrush Market Explorer and BuiltWith cover most of it.
Why it matters
Customers in a market at any moment are shared between you and your competitors, and businesses are valued on market share. Traffic share is the closest public signal of that share, and the channel split shows how each rival wins its customers.
What to capture
| Field | What it tells you |
|---|---|
| Market size | Total value of the category, from research reports or press |
| Total traffic | Combined monthly visits to the competitor set |
| Number of sites | How crowded the category is |
| Traffic share | Each competitor's share of total visits |
| Channel split | Direct, referral, search, social and paid share for each competitor |
| Finding competitors | Sites that compete for the same audience but were not on your list |
Where to find it
- SEMrush Market Explorer: Traffic share, channel split and new competitors in a category
- BuiltWith: How many sites use a technology, which helps size tool and platform markets
- Research reports and press: Market size estimates; compare at least two and note the year
- Google: Search your main keywords to see who shows up that the tools missed
How to do it, step by step
- List five to ten competitors, then add any new names SEMrush Market Explorer suggests for the category.
- Pull monthly visits for each and work out each one's share of the total.
- Record the channel split for each competitor.
- Write down two market size estimates with their source and year.
- Mark the channels where one competitor dominates and the ones nobody owns yet.
Questions this answers
- Who leads the category on traffic, and is the gap growing?
- Which channel does each competitor rely on most?
- Is there a channel nobody in the category is using well?
Do this research in CompetitionOS
CompetitionOS keeps the competitor set for each market in one project, finds new competitors from the Google results for your keywords, and stores SEMrush domain data as evidence with its source and date.
- Find competitors with AI discovery or from the Google results for your keywords
- Keep one shared competitor library across projects, split by direct, indirect and search competitors
- Save evidence with its source: search results, website snapshots and SEMrush data
- Check whether ChatGPT and Claude mention your brand, and which competitors they name instead
- Connect Claude, ChatGPT or Cursor so an assistant can do the research for you
- Export every project to CSV or Excel
Are AI assistants recommending you, or your competitors?
Buyers now ask ChatGPT, Claude and Perplexity which tool to use. CompetitionOS runs the questions your buyers ask, records which brands each answer names, and shows where competitors are mentioned and you are not. That is answer engine optimisation (AEO), alongside your SEO.
Frequently asked questions
What is competitor traffic share?
The share of total visits in a set of competitor websites that goes to each one. If five sites get 1 million visits a month and one gets 400,000, its traffic share is 40%.
How accurate are traffic estimates from SEMrush?
They are estimates built from panels and clickstream data, so treat them as relative rather than exact. They are most useful for comparing competitors measured by the same tool.
How do I size a market quickly?
Take two published estimates for the category, note their year and method, and check them bottom-up: number of likely customers multiplied by what each pays per year.