Half of Podcast Audience Reached by Just 32 Shows, Edison Says.

Many podcasters complain that too much of the ad dollars in the medium are focused on the biggest shows. Magellan AI reports that in the first quarter about $4.80 of every $10 spent on podcast ads went to the top 500 shows. Edison Research has released an analysis that shows why that continues to be the strategy for many of the biggest marketers.

Edison Research says its annual “Infinite Dial” study shows 100 million people in the U.S. are reached by podcasting each week. For advertisers working to calculate how many shows they need to buy to reach half of that audience, Edison says its number crunching shows the top 32 shows have an unduplicated reach of 50% of weekly podcast listeners.

“While advertisements in these podcasts can be expensive, they are a powerful tool in reaching an attractive consumer pool. Advertisers would have to purchase spots in thousands of other podcast titles to reach the remaining one half of weekly podcast listeners,” Edison says in a blog post.

To prove its point, Edison says the data shows it would take buying across the top 3,500 podcasts to reach nine in ten weekly listeners.

“It’s important to recognize that effective podcast advertising strategies often leverage top shows to reach a broad audience in addition to utilizing smaller podcasts to access specific niche listeners with strong engagement,” it says.

In a second research update, according to a recent survey by Edison Research and the Audio Publishers Association, 51% of Americans 18+ have ever listened to an audiobook, accounting for approximately 134 million people. It also finds that interest among non-listeners is also increasing. 

In 2024, one in three (32%) of Americans who listen to spoken word content like podcasts or talk radio, but who have yet to try audiobooks, said they were interested in listening to audiobooks. Edison says that number has now increased to 38% in 2025, with the number of those “very interested” nearly doubling from 10% to 18%. The findings are based on a Feb. 2025 survey Edison Research conducted online of 1,700 U.S. adults aged 18 and older on behalf of the Audio Publishers Association.