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Luis Von ahn
CEO & Co-Founder, Duolingo

The Bridge: 10 Years of the Duolingo English Test | Documentary

📅 Oct 05, 2026 Duolingo English Test 8 MIN 76 VIEWS 21 SEGMENTS · 1 SPEAKERS
What if the world's most accessible learning app built the world's most accessible English test? This is the story of the Duolingo English Test, told by the people who built it and the students who crossed the bridge. Ten years ago, a small team inside Duolingo set out to fix something broken. For millions of talented students, proving their English proficiency and accessing higher education opportunities meant an expensive exam, a long trip to a test center, or no option at all. Many of us had been international students ourselves. So we built the product we wished we'd had. 10 years, 6,500...

What Luis Von ahn said

Written from the verified transcript and checked against it. Every figure links to the moment it was said.

Luis Von Ahn, CEO and co-founder of Duolingo, discussed the origins and mission of the Duolingo English Test (DET). He said the idea came from wanting to help international students prove English proficiency without traveling to test centers, which he described as unfair and costly. Von Ahn noted that Bryce Settles, a machine learning engineer, discovered that vocabulary recognition could measure proficiency, leading to the test's development. He emphasized that validity is the most important aspect of the assessment. He shared that the average distance students traveled to test centers was 175 km, and that taking the test at home is fairer and less expensive. Von Ahn said DET was the main bridge between his family and university, and that he hopes to break down more barriers to education access in the future.

Key takeaways

  1. The Duolingo English Test was created to let students prove English proficiency from home, removing travel and cost barriers.
  2. The average distance students traveled to a test center was 175 km, making home testing fairer and cheaper.
  3. Validity is the most important part of the DET, ensuring the test measures what it claims.
  4. Von Ahn said DET was the main bridge between his family and university, and he saved money for half a year to take a standardized test as an immigrant.
  5. He is excited to prove more 'impossible' things wrong in the next 10 years.

Numbers and commitments

FigureWhat it refers toTypeAt
175 km Average distance students traveled to a test center metric 3:31
11, 12 years ago Time when exploring ideas for a placement test timeline 1:16
10 years Duration of hard work on the DET timeline 7:53

Chapters

  1. 0:00Dream of a home-based test
  2. 1:16Origin of the DET idea
  3. 1:59Importance of English proficiency
  4. 2:22Validity as core principle
  5. 3:04Personal immigrant experience
  6. 3:31Travel distance and fairness
  7. 3:56Leveling the playing field
  8. 5:20Cultural understanding and world peace
  9. 5:50Reflections on the mission
  10. 7:40Future hopes and belief
Luis Von Ahn 0:03 ↗
We dreamt about this when we were kids — to have an option to actually take a test that you could take from home. It's not fair for a lot of people because it depends on where you're born, it depends on how much money you have sometimes, or if you're able to travel and commute to a testing center or not to actually be able to prove that proficiency. So I think that what we want is just to change that, to make sure that people that are talented can have access to those opportunities, or at least we can make it easier for them to have access to those opportunities as well.
If there is no DET, I'm not here. You know, if you want someone like me, you need to accept the DET.
For one, you know, we started a language learning company. Somebody who's grown up in the US and has never left the US, I think, does not understand the power that it is to learn another language, or the power that it is to learn English. And English really changes people's lives. So, you know, the fact that we started a language learning company has a lot to do with the fact that, you know, I was an international student.
I feel like English is that first door that, if it opens for you, it's just going to open so many other doors for you and so many other opportunities for you. It was about 11, 12 years ago when we were exploring some ideas on how to create a placement test for Duolingo. Bryce Settles, who was one of our machine learning engineers at the time, he realized that we can actually measure somebody's proficiency by understanding how well they can recognize vocabulary words. And that was the first item that we developed. After we saw the potential of that project, we also discovered and started chatting about the idea of helping students like we were at some point, and how to prove their English language proficiency.
English proficiency is just so incredibly important because it really opens doors to future opportunities.
Like the original intent when the test didn't exist and we decided that we wanted to make this test, the goals were to have something that was short, that was affordable, and that had a quick turnaround time in terms of how quickly you got your scores, right, and also that you didn't have to travel to a test center.
The most important part of an assessment is validity. We need to make sure that the test measures what we claim that the test measures. With the DET, we designed an assessment that is short, that is adaptive, that is very precise, but most importantly, it is valid.
One of the things that we were very passionate about, and why we were passionate about it, was a lot of the people that were working at Duolingo at the time, and still are working at Duolingo now, are international students. That they had to go through the challenges of having to prove their English proficiency when they were applying to college or getting a job. And it's not a great experience.
As an immigrant, when I had to first come to the US, I had to save money for half a year to be able to take the standardized test that I needed to take to come to the US to study. And in hindsight, if I had a product like the Duolingo English Test, it would have literally saved me months of hard work to access a dream, to access an opportunity that I really needed in my life, that changed my life and the life of my family.
One of the really surprising things that we found when we looked at the data was that the average distance people were traveling to get to a test center was 175 km. It's just incredible when you think about at the end of that you're taking a test and you're probably pretty tired. You might have to stay in a hotel overnight. The costs are racking up. So being able to take a test at home is not only less expensive, it's also fairer to the student.
Students will be less constrained by where they were born or what their families can afford. And so we get to level the playing field. You know, we typically look at a test as just an added transactional product in the journey of studying abroad. But what you realize in most situations, it's the first step that a student takes when they start applying abroad. When you have too many barriers with the first step, that's when you see a lot of students decide that, you know, maybe studying abroad is not meant for them. But as soon as you remove some of those restrictions the way the DET does, suddenly that first step doesn't seem like such a big burden and it doesn't feel as intimidating.
I think one of the reasons why we've done what we've done here at Duolingo, and I think it has to do with the background of Luis, me, Tony as well. We come from a country where there were a lot of talented people, but many of them didn't have the opportunity to actually use that talent and use that talent to get better opportunities. There's people that can buy very good educations and end up getting really good educations, and because of that end up making a lot of money, whereas honestly the vast majority of people don't get very good educations, barely learn how to read and write. And it's very hard to get ahead if you don't learn how to read and write. So that always stuck with me a lot.
Having international students, having home students, and having them all working together is important to kind of help people realize that we're one society as a world, and we can work together in different ways and appreciate each other's backgrounds and cultural histories. I felt really strongly that if people had more opportunity to travel to other places and learn alongside people who are different from them, that it would lead to more cultural understanding of the world, which would lead to something even as lofty as world peace.
You know, when I interviewed for this job almost 10 years ago now, the thing that struck me was the mission of the company behind this test, right? The goal to bring a more affordable, shorter, easier to take — meaning you don't have to go to test centers — test. But then along the way, as I went through each stage of the interview, what really drew me in was the people. The people were really smart, really kind, and that's been true my entire time here. And so I'm really thankful for that. Gosh, I have to do it again.
I would love to see a world where we can just break down more of those barriers in terms of accessibility for people to be able to just pursue their dreams. This work can feel like a drop in the ocean because we know about how much talent is out there, and you know, my God, like what would it be like if we had endless resources to support all of these students? But I think when you think about it in the reverse, there's like a ripple effect too, of like with every one of our scholars, like the impact goes so much further beyond them. You know, not only with their families, with their siblings that are looking up to them, with these communities that they're a part of. That part feels really good, of like knowing that it's much more than just that one student. It's actually a much wider circle.
Sorry.
The biggest difference that we have on the Duolingo English Test and at Duolingo as well is like we truly believe that we can make a difference.
My parents, they actually really wanted me to break that chain and become someone who actually went to college and got a degree and, I don't know, have a better future than themselves. I would say DET was the main bridge between us and university.
Some of these things felt really impossible, or we were certainly told were actually impossible to do, that we've proven wrong. So I think in the next 10 years I'm just really excited to see how many more things we can prove people wrong on too.
It's kind of lucky that we just stumbled on this idea. Some of it has to be luck. The other part has to be hard work, which is what we've been doing for the past 10 years. But also a lot of belief, a lot of belief in that we can change the world.
Heat. Heat.

Cite this transcript

APA, MLA, BibTeX
APA

ahn, L. V. (2026, October 5). The Bridge: 10 Years of the Duolingo English Test | Documentary [Interview transcript]. Duolingo English Test. CEOInterviews.AI. https://ceointerviews.ai/interview/2987179/

MLA

Luis Von ahn. "The Bridge: 10 Years of the Duolingo English Test | Documentary." Duolingo English Test, 5 Oct. 2026. Transcript, CEOInterviews.AI, https://ceointerviews.ai/interview/2987179/.

BibTeX
@misc{ahn2026_2987179,
  author       = {Luis Von ahn},
  title        = {The Bridge: 10 Years of the Duolingo English Test | Documentary},
  howpublished = {Interview transcript, Duolingo English Test. CEOInterviews.AI},
  year         = {2026},
  month        = {oct},
  url          = {https://ceointerviews.ai/interview/2987179/},
  note         = {Speaker-attributed transcript with timestamps}
}