A platform (web and app) offering free language courses for all. 

The app uses game concepts like unlockable levels (lessons) and points and high scores to motivate you to learn a language. 


There are two parts to Duolingo’s brilliant revenue model.

First, they make money by selling translations to companies like CNN and Buzzfeed. So, for example, they write their news in English, and send it to Duoligo. Duolingo then give it to their students, who in order to practice their English skills, help translate this news to their native language. 

The second and most important part is their new app, the Duolingo Test Center. Duolingo is giving everyone the chance to prove that they have language skills without having to pay the $250 normally charged by the existing proficiency tests such as the TOEFL or the IELTS.  Duolingo’s tests will cost $20 and will help their educational app stay afloat.

To get them started and scale, Duolingo has received many investments including a $20 million Series C round of investment led by Kleiner Caufield & Byers and a $45 million Series D round of investment led by Google Capital. 


Place: worldwide

Scale:  200 million people are using Duolingo around the world


  • Knowing English in non-English speaking countries increases job prospects. They can make 25 to 100% higher salary. 


It  all started in 2000 when Luis von Ahn, a professor at Carnegie Mellon University, invented the CAPTCHAs, those verification codes you have to enter on websites to prove that you are human. Around 2005/ 2006,  200 million CAPTCHAs had been used. « At first I was pretty excited, because look at the impact my work has had. But then I realised that this is not a good thing – because CAPTCHA is important, but it does waste 10 seconds of your time, and when you think of the millions of times it gets used, that adds up. »

« So that was when I created a new company and we invented reCAPTCHA that puts that time to good use, and helps to digitise books. I sold that to Google in 2009, but I wanted to do something else that would be meaningful. »

That’s when he teamed up with one of his PhD students (Severin Hacker) and in 2009, the two started Duolingo.

« I come from Guatemala and over there, you will see a lot of inequality, » he says, « because the people who are educated in English have more opportunities and can improve the quality of their lives and they rise, but the people who don’t have that advantage get fewer and fewer opportunities. » (Interview from Gadgets 360)


  • Duolingo started its private beta on November 2011. 
  • In June 2012, it launched for the general public. . 
  • In November2012, Duolingo released its iOS app, and in May 2013 its Android app, which quickly became the #1 education app in the Google Play store. 
  • As of November 2017, Duolingo offered 77  different language courses, with 19 additional courses in development.
  • In 2017, it added Korean, Japanese, Korean, Czech and Swahili, the first African language on Duolingo.


Work for them

As a growing company, Duolingo  is constantly looking for new talents.  Help them build revolutionary new technology that empowers people. They have positions worldwide.