Audience Overlap
Research Intelligence

How to Size Your Market Using Audience Overlap

by Chloe Nicholls , Product Marketing Manager, Similarweb 4 Min.
July 21, 2021

How big is your slice of the audience-share pie? And which other websites is your audience visiting? These are just two of the burning questions that our new, audience overlap feature can help you answer. 

Business-critical tasks for many digital researchers include analyzing total addressable market or audience (TAM), identifying expansion opportunities or similar audiences to attract, plus sourcing potential partnerships. But this can be a challenge when you don’t have the tools or the data to easily size your market. 

Audience overlap lets digital researchers compare up to five websites (like competitors or partners) and measure their total unique visitors and shared audiences for market sizing. 

Six questions audience overlap can help you answer:

  1. What is the % overlap of my audience vs. competitors or partner sites?
  2. What’s my true share? 
  3. What is the total addressable audience online? 
  4. Which player has the most loyal audience for site traffic?
  5. How can I uncover untapped audience growth opportunities?
  6. How can I benchmark my traffic share to my competitors or my industry?

Audience overlap in action 

Audience overlap can show you how up to five websites overlap. 

In the first chart below, you can compare each website directly. Let’s use to analyze how much of the website’s audience also visits competitor (12 monthly average, United States).  

In the example, you can see the total audience between these two players ( and is 8.8 million. 

Each website’s unique visitors and the total number of visitors across the entire group of websites, representing the total unique audience (excluding overlap), are broken down on the right.

Audience overlap feature on Similarweb - shows average unique visitors June-May 2021 for and

Next, hover over the overlap to see each site’s shared audience (average unique visitors) and percentage share. 

Here you can see the shared audience is 592,886 average unique visitors, with 33.7% of’s total audience (1.7 million) also visiting vs. 7.7% of’s total audience 7.6 million. This tells us a higher proportion of’s audience also visits, so at least one out of three visitors goes on to 

You can also add up to five websites, like competitors and, to further understand the overlap between players. 

Audience Overlap Feature on Similarweb - shows competitive set with,, jcrew,com,

By hovering in the center, you can see the shared audience across all four players is 46,000, ranging between 0.6%-4.3% of each website respectively, and the total unique audience is 10.1 million. This means a small proportion of visitors are potential consumers of all four brands.

Pro tip: Export the data from the Venn diagram to explore audience overlap within your own data visualization tools. 

You can also analyze audience loyalty within your comparison. This shows you the percentage of visitors who exclusively visit the site versus two or more sites in one session. The higher the percentage of exclusive visitors indicates greater audience loyalty. 

Website's audience loyalty view on Similarweb - Bar Chart - Gap wins with 81.7% loyalty traffic share compared to competitive set

Here you can see that 81% of’s audience only visit the website during one session over a monthly average, compared to (57%), (46%) and (46%), which demonstrates the strong loyalty of’s visitors towards the brand. 

Finding partnership opportunities with audience overlap

You can also use audience overlap analysis to identify potential partnership opportunities that align with your brand or product offering.

Imagine you’re a digital strategist at the electric scooter company You’re gearing up to launch in the U.K. and want to identify partnerships to promote your new offering and build up excitement. 

Using audience overlap you can quickly and easily identify the total audience you can reach and what percentage of your audience you already share with potential partner brands.

Audience overlap tool showing average unique visitors

Here you can see the total unique audience is 528,000 (12 month period, in United Kingdom) and has the highest number of average unique visitors per month with 279k. also has a shared audience with of 6,900 per month, with at least 12% of their total audience of 56,000 visiting This insight reveals a very high potential for to reach their target audience, plus evaluate the relevance of other media brands to promote the electric scooter product.  

Try out the Audience Overlap tool 

Log into the platform to check out the feature. You can read more about audience overlap here. 

This post is subject to Similarweb legal notices and disclaimers.

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