Duolingo is a hugely popular language-learning app. It’s known for its use of gamification and its passive-aggressive Owl mascot, who is the star of many viral memes. But what you might not know is the pivotal role community played in its breakout growth.
It launched in June 2012 and already had a waiting list of 500,000 people. In a little under 10 years, it became the most used education app on Apple’s App Store and has been downloaded over 500M times  with 21M people using the app daily . They filed for IPO in June 2021 and the company now has a valuation of over $5BN .
Community contribution was key to its early success, and in this deep dive, we’ll take a look at the mechanics of how they inspired those contributions and how that helped drive mass adoption.
✔️ Origin Story: How Duolingo and its Global Ambassador community got started.
✔️ Turning Passion into Profit: The programs that drove contribution and how they used this to unlock user adoption on a global scale.
✔️ Minimum Viable Program: How they create community MVPs and then scale them.
✔️ Return on Community: Member motivations they tap into and the value they create for them.
Here we go! ✨
The idea for Duolingo started in 2009. Then Professor at Carnegie Mellon, Luis von Ahn, and his student Severin Hacker, set out with a vision to make language learning accessible through free education.
Luis is the Godfather of Crowdsourcing . He had recently sold reCAPTCHA to Google. That name is probably familiar - it's those hard-to-read word pairs that websites use to protect themselves from bot spam. But they’re kind of genius. What you’re doing when you fill one in is helping digitize out-of-print books for archives like The New York Times and Google Books.
Luis wanted to repeat this success by creating a free app to help folks learn a language, monetizing it as a crowdsourced translation service. As you used the app, you’d be helping translate words and passages behind the scenes. In that sense, community is built into the core of Duolingo .
That business model didn’t last, but the app was a massive success.
Duolingo is mobile-first. Its courses are fun, bite-sized, and you can dive into them whenever you have a few minutes to spare. Through exercises, you can learn and practice a foreign language to improve your reading, writing, speaking, and listening skills. Oh, and it’s free.
The core of their growth is through word-of-mouth. Around 90% of its users are acquired organically . In fact, between 2011 and 2019, they spent just $15M on external marketing .
It makes money in three main ways: subscriptions (73%) from pro members (around 5% of its user base) , ads (17%), in-app purchases (1%), and English Language tests (9%) . In Q2 2023 that led to $126M in revenue, up 44% from the same quarter last year.
For Duolingo, being freemium is a powerful differentiator. This is interesting because there’s no lack of free language learning resources, as they highlighted in their S-1 :
“We estimate that there are thousands of free mobile applications for language learning; free products are provided in at least 50 languages by private companies, universities, and government agencies."
However, it’s the combination of its high-quality content, combined with the free price point that has led to its tremendous success. Its premium subscription plan doesn’t unlock any new content, it just removes ads and takes away some gameplay restrictions. They give all of their content away.
Duolingo users complete 500M+ exercises each day, generating a huge amount of data that they use to improve the app . As a company, they’re data-driven, testing and optimizing every aspect of their business and product experience. They take a product-led approach through what they call their ‘investment flywheel’, focusing on product innovation and data analytics over performance marketing tactics. The more users they get, the more data they can use to build better products.
“We believe that the hardest part of learning something new is staying motivated, so we build gamification features into our platform to motivate our learners” 
Gamification tactics are often criticized for making products addictive. But for Duolingo, since the outcomes are educational, most users regard their push for engagement as positive. It’s this love-hate relationship with the app that has enabled them to take language learning out of textbooks and classrooms, and into the timelines of social media apps. The Duolingo owl is now a pop-culture icon. Its nagging reminders sent via in-app push notifications are the focus of viral TikTok videos and Twitter memes.
They don’t shy away from this. Their promo video for an April Fools’ Day prank, which plays off such memes, has been viewed almost 8M times on YouTube.
What’s most interesting to me, though, is how Duolingo used community to drive growth, engender advocacy, and refine its products. And then shut it all down. Community served a pivotal purpose for Duolingo and was a core part of its corporate strategy. While most of those programs are no longer operational, there’s much we can learn.
The community at Duolingo became known as Duolingo Global Ambassadors. Laura Nestler, Global Head of Community between 2016 and 2021, describes the community as :
“A wide-reaching and passionate group made up of Contributors (who create and maintain all of our language courses), Hosts (who hold offline language events in cities around the world), Moderators (who answer language questions and keep our online forums safe), and Educators (who use Duolingo in their classrooms).”
What Duolingo did exceptionally well, was understand how to channel the energy of this passionate user base, and direct it in ways that helped push forward the mission and goals of the business .
To that end, community activity was focused on three main things:
We’ll take a close look at each of these aspects and pull out the common approach that underpins them. This approach is a generalizable process that you can use to help drive contribution within your community.
Shortly after Laura joined Duolingo, they rebranded the community, giving it the name ‘Duolingo Global Ambassadors’ : “We just needed a culture and engagement refresh for our community. Then we needed to focus on doing a better job connecting our staff.”
Connecting staff to community meant giving them a better understanding of the people that the community was impacting, and how they were doing it. “So I started this mission of not only telling stories internally but actually just going out and actively trying to find these stories” .
This wasn’t some fluffy feel-good exercise, but part of a strategic plan. As Laura says, “In order for your brand's community to yield maximum benefit it really needs to be structured as a high-level strategy impacting business-wide goals” . So the plan was to make it clear how their community-driven model was not a cost center but a growth center that enabled the company to scale .
What I love about Laura’s approach is that she not only appreciates the value that community can deliver and the importance of building relationships, but she’s a strategic operator as this candid statement shows:
“If you're just beating the drum of, we need more… this isn't working. You don't believe in us. You can start to sound a little bit victimy.”
She knew she needed to change the way people thought about community as a function within Duolingo, so she set about finding quick wins. One was helping with product quality, which was a concern for some teams she spoke with. So Laura set about “giving our community members access to test builds. Because from the internal perspective, they would love to have eyes to help bug bash. And from a community perspective, they would love to have early access to our products and our features. So that was a win-win” .
Next up, “I just ruthlessly prioritized areas of our community that I thought could deliver measurable impact… The first one was just diving in on this idea that our community was building the content that was then being consumed.”
Duolingo created the first four language courses themselves utilizing teams of in-house experts. They then took what they had learned from that process and recruited hundreds of community members to create future courses. As Laura points out, this was a bold move :
“It takes guts from a company to be willing to say we're going to put this essential component of our business in the hands of our community”
But that’s exactly what they did. They took that core part of their product, and opened it up to volunteers, launching Duolingo Incubator in October 2013.
Incubator gave volunteers the technical tools they needed to design and create language courses. Contributors are provided with a template course, they then decide on the sentences, word structure, and skills necessary to develop a course  and were free to form their own teams . Alongside this, their in-house experts transitioned into community manager roles, helping to vet members for language proficiency as well as mentor and unblock community volunteers .
In opening up course creation in this way, and by tapping into the skills and passion of hundreds of its members, they could create and test high-quality content at scale without huge costs.
Over the next 8 years, 1,000 volunteer contributors came together to collectively create over 90 new courses in 37 languages .
The business benefit of this was huge. Many learners have a specific need or reason to learn a language. Any language won’t do, it has to be a specific one. As such, course availability and language support is a major bottleneck to Duolingo’s growth. Every new language that gets a course adds to its Total Addressable Market (TAM).
According to Kristine Michelsen-Correa, who was Head of Community from 2013 through 2017, course creation was the number one driver of new user acquisition in 2014 and continued to boost growth for years to come .
Crowdsourcing courses meant Duolingo was able to add more content faster than their staff capacity would allow . In fact, by the end of 2014, they had launched 39 new language courses  servicing 50M active users , and all with a team of less than 40 people.
Developing each course was still quite an undertaking. The average time to create a course and get it ready for beta was three months . Volunteers would spend an average of five hours per week contributing, although this was up to 20 hours in some cases . Laura is quick to highlight though that “even though our courses are developed and maintained by our volunteer community, it still takes a significant amount of staff resources to execute a successful launch and sustain a course” . It certainly brought the whole company and community close together, at least early on, as Kristine mentions :
“The entire Duolingo team is constantly interacting with our community. Even the engineers are involved in this process and they’re all known by name within the community.“
Slack was used for course creators and staff to collaborate . They’d share global announcements and members would share course ideas, pictures, tips, and motivational gifs. Each team would also have their own channel to chat and build camaraderie. Members used this shared space to compare their progress to other teams, engendering some healthy competition .
The program worked so well because members loved it too. As Laura says, with “community they're most vibrant when they are actually impacting what's being made” . Course creators were at the center of its burgeoning global success. Duolingo’s mission became their mission, and the impact they were helping make happen was transformative in some cases.
The community model meant they were able to further the mission of making language learning accessible to all, and enabled them to work with communities like the Navajo, Hawaiian, Welsh, Maori, and Gaelic to create courses of their own. The service was personally thanked by Ireland President Michael D. Higgins for an “act of both national and global citizenship,” highlighting that three-quarters of Duolingo Irish students are from outside of Ireland . Given the relatively small sizes of these endangered languages, without the community contribution model, it wouldn’t have made business sense to invest resources in such courses .
The success of this contributor program gave Laura the social capital within Duolingo to expand the remit of community, and it was then that they moved into events too .
There’s a retention issue baked into language learning platforms. What do you do after you’ve completed the courses for the language you’re interested in? Some may move on to another language, sure, but most won’t. It was tackling this that led Duolingo into events .
Duolingo Events launched in 2017, helping learners build their speaking confidence by getting them together with other learners to practice . At first, this was face-to-face, but it spread to online video calls later, too .
It proved to be a great fit for Duolingo and its community - language learning is a social activity and people learning a language are always on the lookout for ways to practice. Plus, it helps to build brand loyalty and differentiate the Duolingo ecosystem from online-only competitors .
As a community strategy, in-person events can be a powerful thing. As Laura explains :
“It's tangible. It's palpable… A lot of people really want to squeeze whatever quantifiable metric they can get out of them… But that's not the point. The point is that you are operationalizing your mission and your brand. You're connecting with people who are physically in-person and experiencing what you have to offer.”
They were a hit. By 2019 they were organizing 600 events per week across 113 countries and 820 cities, covering 34 different languages . From Italian in Shanghai to Esperanto in Orlando, at its peak, they were at 800 weekly events.
The addition of events showed that fostering real-world connections between users can boost platform engagement and help drive sustainable growth through advocacy.
In addition to course creation and events, the Duolingo community came together around its peer-to-peer knowledge-sharing forum that had over 1M members . Language learners would discuss course content, provide product feedback, and get into the nitty-gritty nuances of learning a language.
The forums were organized by language  and learners would share tips and resources to help each other . It was here where many of the community’s rituals, memes, and jokes would emerge. Laura says that this is like gold dust for community managers :
“Your role is to pay attention and amplify these messages and practices when they reinforce group identity and align with your brand’s goals.”
Doing this is not only good for building relationships between members, but it can help drive growth too. Remember the owl mascot meme they created the April Fool’s Day campaign around? That drove 8M social impressions. It was their top-performing campaign at the time with millions of YouTube views and 600 press hits. That exposure led to a 70% increase in new users on iOS and 55% more users on Android. And it all came from a meme that was generated and perpetuated by their community . As Laura suggests, “If your community starts organizing events, reach out to the organizers and offer your support. If your community starts a recurring joke or meme, lean into it” .
The business benefit of this approach is clear as Duolingo states in their S-1 filing: “Owned media marketing engages our learner community, creating millions of brand advocates who drive word-of-mouth virality by sharing their love of Duolingo within their networks” .
The forums are also where the community team would hear many of the stories members would share about the impact that Duolingo and language learning was having on their lives. Such powerful stories led them to create a documentary called “Something Like Home.”
The film tells the stories of refugees who had fled war-torn areas of the Middle East but had found hope again after resettlement by learning new languages. It was the result of a grassroots collaboration with a local photojournalist and premiered in a theater across the street from Duolingo’s Pittsburgh-based HQ . The film was a confluence of community and the Duolingo brand and mission. As Laura says :
“Community at Duolingo is not just a fuzzy buzzword, it's the mega highway that connects what we do, why we do it, and who we do it for.”
When it comes to community-led growth, building a thriving community is only part of the work. Laura points out that the rest is about making sure the outcomes of that community create value for the business too : “It’s about understanding how channeling this energy and enabling it can help push forward the mission and the goals of the organization…. We have to hold our programs to the same rigorous set of standards as any other internal org or function and know that our priorities have to align with the greater business.”
This is what Duolingo mastered when creating community programs, and they built a reproducible process around it. Let’s step through the key elements.
The process takes inspiration from lean business and product development practices, trying to cheaply test out a concept, discovering what works, and then scaling from there :
“Community managers often are seen as like party people, you know, or people that are just kind of there cheering people on from the sidelines. But really, it's a science. And if you follow steps, if you create processes, it can be repeated and scaled.”
The process they used for course creation, and then refined when adding in events, has four main phases:
You do the thing yourself and you document everything along the way.
“I'm going to document the email that I send to people. I'm going to document the response that I send when they RSVP. I'm going to document the email that I sent to the business to reserve my space.”
The resulting notes are the beginning of the playbook you use when rolling this program out at scale . Over time this develops into a Wiki and a set of canned responses , and later still, it becomes your community guidelines and norms that set volunteers up for success .
But first things first, just start. With events, Laura began the program in her hometown of Seattle, sending an email to 500 locals  and spinning up a Google form so that they could RSVP . The key thing during this phase is to just do it yourself and learn what the pain points are.
Now it’s time to do things that don't scale. To test out ideas and perfect whatever it is you’re doing. For Duolingo events, for example, Laura says they ran upwards of 40 tests trying to perfect every little detail :
“I tried afternoons. I tried bringing in a tutor. I tried meeting at libraries. I tried meeting at bars. I tried sending information beforehand… I tried partnership. I tried talking to WeWork.”
The metric of success they were measuring their tests against for events was retention:
“I throw an event one week, the next week, how many of the people that were there the first week come back?”
And then with each test, you can judge whether this is actually adding value for people. Laura says, “If it is, you should be able to see indications of growth… and if it stays at a plateau, it's probably time to go back” and keep trying . They supplemented these test results with feedback from event attendee surveys. Most of your ideas won't work and that's part of this process, so you need to learn to get comfortable with that .
Laura set herself a challenge: “I said, okay, well, I don't speak French. I'm going to see if I can get a host to hold French events for me. And as soon as I was able to crack that, as soon as people that were coming would not only come back but also volunteer to hold events in the language that they spoke more fluently. That's when I knew it was time to invest more deeply.”
At each iteration, you’re optimizing your process for the next order of magnitude. So for events, for example, Laura says, “Run five events yourself. You figure out a process and a system that works… then once you've done those things, you can grow to 10 cities. You can grow to 50 cities. You can go to 100 cities” . You’re not building the perfect program in one go, you’re building it out over time as you’re learning :
“You just build what you need to get your airplane in the air, you worry about your in-flight entertainment options later.”
They replaced their Google form with Meetup, which got them to 10 events per week. Down the line, they switched to Bevy when they were targeting 100 events per week .
It took them around 6 months to get to that 100 event-per-week rate . Over those 6 months, they held over 900 total events in 240 cities and 60 countries . By the end of the first year, they were at 500 events a month, and by the end of year two, they were at 500 per week. They kept iterating, topping out at 800 events per week . Then during COVID, they pivoted events online, and in doing so increased RSVPs by 40x and built out their own event tech stack to support it .
For course creation, while they ended up with a training program, a vetting process, and a swanky application system, they got started in a similarly lo-fi manner. They built out some tools, which Laura describes as “janky”, “ugly”, and “pretty painful for everybody involved” 😅 . They supplemented this with high-touch support from their community management team, which they knew wouldn’t scale, but it got them the answer to the question they needed: Would the community build the courses? Only once this was a clear “yes”, did they start to build out systems to help them scale. Laura reminds us that, “if you're solving a real problem, you do not need a fancy suite of tools” . Instead, they iterated on the toolset for course creators over time, using a UserVoice board for feedback and voting on feature requests and bug reports .
Given the scale at which the Duolingo community operates, automation is key. For course creation, this was particularly important given the complexity of what they were creating.
During the creation of the course itself, there were three main phases, each with metrics you needed to achieve before you could continue to the next one :
Learners can report errors from within the app. Over 200,000 such reports come in each day . They leverage their data science expertise to prioritize issues raised through the Report Quality Estimation Tool they created . Course creators would then look out for reported issues in Duolingo Incubator and could improve the course over time based on this feedback. Course creators were also free to add new lessons, words, and phrases as necessary. In some cases, they would even create a second course and A/B test it to see which led to better learning outcomes . This collaborative approach to course quality assurance ensures that standards remain high despite the range of skills and abilities among the large team of contributors.
They also created something called the Workshop, which was a toolbox for course creators. It gave them tools to bulk edit sentences and other tools to make course creation easier .
Other examples of automation include routing event feedback to hosts, so they were able to see what they needed to improve . They integrated event signup with their CRM so they could have preset emails go out at each stage of the onboarding process. This meant they could automate common tasks like getting their code of conduct signed, and the printing of name tags and stickers for events .
The point of this automation was to free up community team members from worrying about the little things that don’t directly create value in the lives of the people they were supporting .
Laura cautions, that this MVP process “is a slow and measured approach, and it requires that you’re not precious about your idea. If you’re proven wrong (and when, because it will happen), you must realistically assess whether you’re solving for a real problem” .
What’s more, you can’t shortcut it. The model only works if you deploy the right motivations in the right way :
“It's really tempting to want to hack community growth with incentives… but community is not transactional by nature. Humans seek to connect on a deeper level. They're looking for validation or for support or for something bigger than themselves.
And now that community is such a buzzword, everyone wants it and they want it quickly… but when you growth hack with incentives, what you gain in volume, you erode in authenticity.”
So there’s pre-work you have to do before getting into the MVP design itself, and that’s to work out what the right motivations are for your program. For contribution, this is distinct from the motivations of your wider community. In the classic 90-9-1 rule of contribution, you’re focusing on what matters to the 1%.
As Kirsten notes, “a lot of people talk about the power of swag… but for volunteers, it goes way beyond that, it goes into understanding why people are contributing . Focusing on the right people here is like the inverse of the traditional marketing funnel , and Laura says, “There is nothing more important than your leaders in any community… they are the driver of all of your success” .
Like in the Airbyte deep dive, a big vision was a key motivator for inspiring contribution. For those who value language, Duolingo was building a platform with the potential to enable language learning on a huge scale, and that alone was something many people wanted to be part of. But there was a wide range of other reasons members had for getting involved. Some wanted to preserve languages from going extinct, while others wanted to help people speak the language of their country. Some wanted to connect with folks from different cultures, and others wanted to help maintain knowledge of a language they had already learned .
Duolingo was also careful to structure its programs in a way to allow for key intrinsic motivators, such as autonomy, mastery, and purpose :
They supplemented these with extrinsic motivators, too. They would hold events for contributors, like the Incubator Summit, which brought together volunteers from around the world for a day of learning . They also ran Q&A webinars for all Global Ambassadors whenever a new app feature was going to be released, giving them exclusive early access .
In some cases, community team members would provide members with recommendations for college, graduate school, or jobs. There was recognition too. Course creators, for example, were identified by name on a course page in the app . The community team would make thank you cards, write notes, and do video calls thanking members for their contributions: “We were constantly thinking about authentic ways to thank our volunteers,” remembers Kirsten .
Importantly, the different programs provided for a range of contribution levels. While course creation or event hosting would be a lot of work, members could instead opt to help moderate the forum or sign up to be a course beta tester .
The community programs at Duolingo have now been shuttered. Courses are now made internally but the course creation program ran for 8 years right up to their IPO in 2021, and events ceased then too. The forums were closed a year later, on March 22, 2022 .
By way of explanation for their closure, Duolingo highlighted that they “now make money from our courses. This was not the case when the Incubator was opened to volunteers… it does not feel fair and equitable to continue this gracious relationship.” They go on to say, “We have standardized our approach to creating and updating our courses. There are now strict timelines and specific templates around delivering course content, which cannot and should not be applied to volunteer Contributors who do this as a passion project, not as a job” .
When community programs get closed, it’s often abrupt and will little planning. Here it seems there was a little more thought and consideration. As part of the shutdown, volunteers were offered paid positions within Duolingo in some cases. They also established the Duolingo Language Impact award – a $4 million fund that was shared among the community, along with some additional recognition and VIP event access .
The community lives on for some at least as a strong community emerged on Reddit effectively replacing Duolingo’s forums . Duolingo also highlighted the unofficial Duolingo Discord server in their shutdown FAQ .
Regardless, the programs served a significant role in growing the Duolingo business. When they started, as a small company, it was the only way they could scale course creation and make language learning accessible to hundreds of millions of people . Their events hit on a core retention problem and they ensured the business impact of their programs by building out MVPs and scaling them over time.
That's it! That’s how Duolingo used community contribution to build its business. For more details, check out the sources below. If you found this useful, please share it with friends and colleagues, and don't forget to subscribe below. ✌