As startups do every once in a while, we need to convince a group of complete strangers with no background in podcasting that the industry is going to be massive. It’s a time to look skepticism and the naysayers in the face and say not today, not today.

In our case, it’s judging the size of the podcasting advertising market and looking at the supporting technologies and markets needed to validate our assumptions.

The IAB recently looked at the podcast advertising market in their 2018 Podcast Ad Revenue Study. They found it grew 34% year over year from 2017 - 2018 from $313m to $479m. The IAB went on to say that the podcast industry would reach $1 Billion in 2021.

Great news all around everyone, but that didn’t stop the “experts” coming out of the woodwork to put the industry in the ground. Great headline in this piece, but Billy’s entire argument is based on the predictions of the IAB.

Let’s look at how good the IAB’s predictions about podcasting in the past have been.

In the IAB’s 2016 Full Year report did not take into account the full size of the industry, just those who reported. They predicted self-reporting to rise to $220m in 2017. The 2017 report came out it put this number at $257M.

In IAB’s 2017 Full Year report they predicted the market to rise to $402M. In the 2018 report, it hit $479M.

These predictions are hard, and I’m not shaming the IAB. What I am saying is the IAB consistently underestimates the future size of the podcast advertising market. For 2017 and 2018 the IAB was under by an average of 15%.

If you base your entire argument on the IAB’s report, you are doing it wrong. Instead, let’s look at the underlying markets, growth in other sectors and decide if podcasting has the headroom, inventory, and delivery mechanisms to sustain its current ~30% YoY growth.


Everyone is in agreement that the market will cross $1 billion around 2021. The question becomes, what happens after that? The following plots three growth curves: IAB Predictions, Podsights Predictions, and Blow the Roof Off This Thing predictions.

YoY Growth is going to decay. Adding $100M to the market to get 40% growth is not the same as adding $500M to get 20% growth. The question is, how fast will it decay? IAB thinks we have two more years of 20% growth, and then the ship starts to slow.

If you take the long on podcasting and history tells us IAB predictions are conservative, you get the Podsights model. Growth in the 20% range over the next five years, then tapers down. We aren’t the only one with this model.

Neal Shore, the CEO at Triton Digital, said the following:

“I believe that podcasting will be here for a long time, and that revenue will ramp up quickly. I see podcasting becoming a billion-dollar market in 2020 or 2021 and a $3-billion market by 2023.”

The man is even more bullish than us. For these predictions to hold, the money needs to come from somewhere, and the audience needs to show up. We will start with the money.


I think that we all lose sight of how much money is sloshing around the global advertising markets. Radio Advertising was $17.8B in 2018 and Digital $107.5B. If podcasting were to take just 4% of radio and digital spend, it would be a $5 billion dollar industry overnight.

There is no doubt that the ad dollars are there to support growth, it’s whether podcast advertising can be compelling enough for brands to move budgets around.

If you’re into the Mary Meeker decks, she outlines a reason for a shift. Competition on digital networks like Google and Facebook is pushing up CPM and CACs for everyone. As Meeker points out: “CAC Can’t Exceed LTV for Very Long.” As advertisers seek cheaper harbors, they will find podcasting alluring.


The inventory is just there. We have heard time after time that publishers are leaving 30% of their inventory unsold month after month. We have talked about churn before, so publishers need to find a constant stream of new advertisers to fill their placements.

What you are seeing now is solutions like Megaphone’s MTM and Acast. Publishers are allowing their hosting providers to fill their unsold inventory via targeting.

Ad Tech

The broader shift will come when the long tail podcasters more broadly adopt dynamic insertion. It’s a widely held belief that of the 700,000 podcasts only the top 15,000 or so podcasts are monetizable. There is just too much back and forth with small and independent podcasters to buy at scale.

Dynamic insertion solves this problem. If I can bundle a hundred podcasts together, it becomes a more efficient market.

The other hurdle is proving these ads work. Reporting and attribution have long been absent from podcasting and Podsights is actively trying to solve this problem.


There is a running joke that three white guys with average opinions are the basis for all podcasts. These idiots might be starting a podcast, but those who are succeeding are doing something much different.

Gimlet is working on Motherhood Sessions, The Nod, and Two Prices. Pushkin Industries has your high brow sophisticated content, Barstool succeeding going in the opposition direction. Wondery continues to churn out shows that will eventually make it to TV. HBO has a companion podcast to Chernobyl that did really well. The Ringer did Binge Mode: Harry Potter.

The New York Times, Bloomberg, Slate, The Washington Post, etc. continue to invest in podcasting. iHeart, PodcastOne, Westwood continue to transform celebrities into podcast ad dollars.

Brands such as MailChimp are investing in their own productions to deepen relationships with consumers.

For podcasting to continue to grow, it’s going to need to continue to diversify its content and audience. Ten years ago, listeners were 73% white, and in 2018, that number is down to 53%. Content + audience is trending in the right direction.


Lastly, we need the podcast player ecosystem to improve. Spotify is taking the lead here. 2018 Spotify played podcasts, sure, but 2019 Spotify has no chill. They now own Gimlet, Parcast, Anchor and apparently have a few more tens of millions to throw at podcasting.

Apple is breaking up iTunes and getting dedicated spaces for podcasts and a desktop app. Google launched their podcast app but also decided to run every single podcast episode through speech to text to put into Google’s search engine.

Himalaya wasn’t done just conquering China; they are coming for the US. Swoot, Brew, Breaker, and Scout all have high hopes for their parts of the player market.

We all also decided to let a little podcast player listen to our daily lives. Alexa and Google Home continue to have the untapped potential of growing the podcast market.

Pandora is also somewhere in there. Luminary seems like they are just keeping their heads down, which makes the “days since last PR incident” sign happy.

It’s hard to make a 10x podcast player experience. I don’t know who’s going to win if anyone. I do know that competition in this space should make the podcasters happy.


Predictions are just that, time will tell. What I do know is that advertising vets have been betting against podcasting for a long time, and every time podcasting beats them.

What I’m trying to say, is don’t be Billy, take the long.