How did the American educational app "Duolingo" enter and succeed in the Japanese market?

Currently the most downloaded app in the education category in Japan, the American-born app "Duolingo".

Many people have likely seen the commercial where the green owl mascot, Duo, rolls around to the tune of the "Duolingo Roll Roll" song.

Despite this, when Duolingo fully entered the Japanese market in 2020, its awareness was below 5%. By 2025, awareness has surpassed 20%, and daily active users have increased more than tenfold. This growth was significantly driven by Dentsu Inc.'s meticulous media planning and creative work that resonated deeply with Japanese audiences.

This time, we interviewed Sho Mizutani, Duolingo's Japan Market Manager, and Keisuke Okuno from Dentsu Inc., who handled the creative for this project. Taichi Arakawa, Business Producer at Dentsu Inc., serves as the interviewer. They look back on Duolingo's journey so far and how Dentsu Inc. supported them, focusing on the behind-the-scenes story leading up to the broadcast of the "Duolingo Goro Goro" TV commercial.

The Challenge Starting from 3.8% Awareness. Why the Focus on TV Commercials?

Arakawa: Mr. Mizutani, you joined Duolingo in August 2020. That was around the time of the full-scale entry into Japan. What challenges were you facing at that time?

 

Mizutani: As of March 2021, Duolingo's awareness in Japan was only 3.8%. The fundamental challenge was that people simply didn't know about us. On the other hand,

• even if people were aware of the app, they were highly likely to use it

• and users who did know about it were highly likely to stick with it

That's precisely why the path forward was clear: we needed to focus first on boosting awareness. Within that, I had wanted to do TV commercials from the moment I joined.

Arakawa: Why TV commercials specifically?

Mizutani: One reason was my experience with TV commercials for an app I worked on at my previous job. That experience made me realize, "TV is the way to boost app awareness," and I felt its effectiveness firsthand. Another reason was that I believed the Duolingo product itself was well-suited for TV commercials.

Duolingo isn't just popular with younger users; it's embraced by people of all ages and genders. We also knew that among the older demographics, who tend to watch more TV, once they started using the app, retention rates were high. That's why I felt TV commercials were a natural fit from the start.

Arakawa: For apps expanding globally, I imagine creative assets are often standardized across countries. Why did you choose to create Japan-original creative assets?

Mizutani: Duolingo does run TV commercials in the US, but their content leans more towards branding than app awareness. Plus, they're made with very distinctly foreign-looking 3D animation. We felt it was necessary to create original content for Japan rather than simply using the US creative as-is.

Arakawa: Okuno-san, you've been the Creative Director for Duolingo's commercials since the beginning, right? What led to your involvement?

Okuno: I've known Mizutani since his previous job. What still sticks with me is when I asked him why he joined Duolingo.

"Duolingo's mission is to eliminate educational disparities and create a world where wealth doesn't determine access to education. I want to dedicate my life to making the world better,"

That made me think, I have to help with this!

Later, as we discussed strategies together, we decided that to boost the app's recognition, we should first focus on promoting the name "Duolingo." So we created a web video. We composed an original song using the phrase "Duolingo-ro-ro," which ultimately became the seed for a TV commercial.

"Duolingo-ro-ro-ro" was inspired by users enjoying it in the bath.

Arakawa: Where did that memorable phrase "Duolingo Logoro" come from?

Mizutani: It came from something I noticed while conducting many interviews with Duolingo users. In those interviews, I often heard users say Duolingo's value was "convenient because you can use it when you wake up or before bed."

Among them, one man mentioned, "I've been using Duolingo every day in the bath for two years." It didn't particularly stick with me at the time, but later, upon reflection, it struck me as odd. Why would someone deliberately study during their relaxation time? I became curious.

So I called that man again and asked why he used it in the bath. He didn't seem to know the reason himself, but when he mentioned, "I used to scroll through Instagram in the bath," it hit me: Duolingo was being used in the same way as reading manga or checking social media!

In other words, Duolingo's benefit lies in letting you learn languages even during those relaxed, zoning-out moments. I thought you could also call it "an app you can learn with while lounging around."

When I shared this with Mr. Okuno, "Duolingo-Goro-Goro" was born. Ah, so that's how it could be done! I found myself laughing alone when I first saw the video (laugh).

Okuno: The "Go" in "Duolingo" and "Go-ro-ro" linked up, so I thought this would be easy to create. But for me, what was even better was being able to focus on conveying the core message.

Duolingo is free, lets you learn over 40 languages, has game elements... it has so many features, and I'm sure there was a lot they wanted to communicate. But they held back, focusing solely on the naming and conveying the app's core value. was a good choice for the initial creative.

Convincing Headquarters with Thorough Research! Demonstrating TV Commercial Effectiveness with Numbers

Arakawa: First, the "Duolingo Gorogoro" web video was created, and then the TV commercial aired nationwide in May 2022. I imagine there were many challenges leading up to its realization. Wasn't it difficult to convince the US headquarters to even want to run a TV commercial on Japanese terrestrial broadcasts?

Mizutani: Exactly. The fundamental issue is that TV commercials haven't performed well in markets outside Japan and South Korea. So, from a global perspective, the initial question is always, "Why TV commercials?" TV ads are extremely costly, and often don't deliver results. Especially for a product like an app, many global companies are hesitant because they see it as not justifying the cost compared to digital advertising, where effectiveness can be tracked.

The reason TV commercials work in Japan and Korea is that, despite talk of people turning away from TV, people still watch it significantly more than in other countries. Another reason for Japan is the limited number of channels. In places like the US, cable TV is mainstream, but with over 100 channels to begin with, the audience gets fragmented.

Arakawa: Japan's media landscape, with its limited number of TV channels, is unique from a global perspective. How did you convince them?

Mizutani: The ability to conduct test marketing in regional areas before the national TV commercial broadcast was a major persuasive factor. Actually, during the initial test marketing, the planned creative wasn't completed in time, so we used different global materials. However, we couldn't give up there. We conducted additional tests and persistently negotiated with headquarters, asking for another chance if the scores significantly outperformed the initial test results.

We tested several video patterns, including "Duolingo Gorogoro," and ultimately decided to produce the TV commercial using "Duolingo Gorogoro," which achieved the highest scores. In the end, the CPI (※) also dropped to about one-third of what it was during the initial test marketing.

※CPI = Cost Per Install. The cost per app installation.
 

Arakawa: Before running the TV commercial, we gave a final presentation to Duolingo's media director, with Dentsu Inc. also involved, right?

Mizutani: We already had results exceeding the test marketing scores, so we had the green light from the head office management. However, the head of the media department remained skeptical about the TV commercial right up until the end. That's when we brought in a Dentsu Inc. media planner. Tosuke Yoshioka , we created presentation materials and held a meeting with our global team.

We explained the Japanese media landscape and discussed the nationwide CPI for "Duolingo Gorogoro," calculated from regional test marketing results. Mr. Yoshioka answered every question with quantitative data, which was very persuasive.

Another highly effective element in our explanation was leveraging Dentsu Inc.'s solution, "STADIA" (*). Using "STADIA" allows us to see exactly how many people who saw a TV commercial downloaded the app, down to identifying the broadcasters, programs, and time slots with the best performance. This made it extremely effective as persuasive material. This kind of TV viewing log data and its effectiveness measurement is data that cannot be obtained globally, so it was also highly valued back in Japan.

※STADIA = Dentsu Inc.'s integrated marketing platform for digital ad delivery and effectiveness verification based on actual TV viewing logs. It enables combined analysis of TV and digital, which was traditionally difficult to measure.

Another significant factor was that, in addition to TV commercials being effective in Japan, there's a secondary effect: "During TV commercial campaigns, digital ad CPI also improves." In other words, once an app is seen in a TV commercial, when users later encounter it through digital ads, a sort of "halo effect" kicks in – they recognize it as "the app I saw on TV." We also presented actual test figures demonstrating this.

Thanks to this detailed analysis and explanation, we gained internal understanding, including from the head of the media department, enabling us to secure nationwide broadcasts.

Thanks to the success of the TV commercials, we became the #1 app in the education category.

Arakawa: The TV commercial was a huge success in the end!

Mizutani: Yes, internally it was recognized as "the biggest success of this fiscal period in Japan," which was a huge relief for me personally. On the App Store, our download ranking skyrocketed from around 100th place to 3rd, and our awareness rate, which had been a challenge, rose to 16% by June 2023. Subsequently, daily active users exceeded ten times the level from our 2020 Japan launch by 2024. From 2023 to now, we've grown to become the number one app in the education category for both downloads and revenue.

Okuno: After that, we produced several national TV commercials, right? In 2023, we decided to create a "Duolingo Goro Goro" commercial with even higher animation quality, working with director Koichiro Tsujikawa to refine every detail into a polished animation.

Mizutani: This commercial was very well-received internally for its high quality, and everyone, including our creative team, really loves it!

Okuno: We've also built a strong relationship with James Kuzinski, Duolingo's global creative director, over the years. There are differences in creative approaches between Japan and the US. For example, 2D animation is mainstream for commercials in Japan, while 3D is more common in the US.

I also noticed a slight difference in how "cute" is perceived. Duo, the green owl, is a universal character across Duolingo's world. When I first saw him, I thought he was cute. But in the home country, he's more of an "eccentric" character. If you slack off on learning, he'll nag you persistently, like "Still not doing it?" or "Today's almost over!" and even get angry (laughs). We explored these differing perceptions of the character together, explained things to the home office, gained their understanding, and gradually aligned our approaches.

Looking back now, though, I'm glad we made a commercial that conveyed Duo's cuteness right from the start. I'm really grateful that James understood that point so well. If we'd gone full-on Duo from the start, it might not have been well-received in Japan (laughs). That said, over five years we gradually brought the character closer to the global standard for Duo. I think the live-action commercial aired in 2024 successfully conveys Duo's unique personality, not just cuteness.

  Mizutani: Of course, the CM's numerical results are important, but the quality of the creative work itself, handled by Okuno and his team, is high, and they have a deep understanding of the character. I believe this has earned them the trust of our creative team.

And it's not just the creative work; I feel a deep trust in Dentsu Inc.'s media planning as well. Initially, we held kickoff meetings with Dentsu Inc. before TV commercial airings, where Mr. Yoshioka and his team would explain the media plan simulations and analysis results. But gradually, that became unnecessary. That's because upper management started saying, "They (Dentsu Inc.) are 'maniacs,' so they'll be fine now" (laughs).

Okuno: "Media maniacs," huh? (laughs)

Mizutani: Also, even after the campaign ended, thanks to STADIA, we could have constructive discussions about the next campaign. For example, since the "Duolingo Logoro" commercial performed better on weekends, we could plan to create creative content that would be effective on weekdays next time. This point is also highly valued internally.

The key to entering the Japanese market is thorough preparation of media plans and creative

Arakawa: Looking at the success of this Duolingo case, I'd like to ask about key points for global companies entering Japan. What are your thoughts, Mizutani?

Mizutani: First, I believe preparing a meticulous media plan is crucial. In this case, Dentsu Inc. deeply understood Japan's unique media landscape and conducted detailed analyses using tools like STADIA. This instantly earned the trust of our internal team from the start. As a result, securing budgets and moving forward became much easier after "Duolingo Logoro," right?

Regarding creative work, I felt it was vital to share as concrete an image as possible with headquarters due to the language barrier. Text-only explanations or sharing reference videos alone sometimes fail to convey the message accurately. For the "Duolingo Logoro" creative, we were fortunate that Mr. Okuno initially created a video storyboard that included the song, making it much easier to share the vision internally.

Overall, I believe that thoroughly preparing concrete materials for both the media plan and creative assets from the outset makes it easier to persuade headquarters and get things moving.

Arakawa: Thank you! Finally, could you share Duolingo's future outlook in Japan?

Mizutani: Currently, the US has the most users and generates the highest revenue for Duolingo. Our current goal is for Japan to surpass that position, and our CEO also hopes for this.

Market-wise, this is entirely feasible. We see significant potential in the English learner market, particularly across Asia, including non-native English-speaking countries like Japan. Japan is also a crucial country for Duolingo's future strategy. We will continue our efforts to expand our user base.