The Finance Corner

The Finance Corner

Deep dive into Duolingo

A new addition to the portfolio

Kostadin Ristovski, ACCA's avatar
Kostadin Ristovski, ACCA
Oct 31, 2025
∙ Paid
File:Duolingo logo.svg - Wikimedia Commons

Duolingo is a company that those who use traditional valuation metrics will completely ignore.

Why would you do a deep dive into a company with a Price-to-sales ratio of 14 and a Price-to-earnings ratio above 110?

The answer is simple: Growth. Disruptive growth.

I believe Duolingo has a significant chance of outperforming the market in the long run, which is why it is the latest addition to my portfolio.


1.0 Introduction

Back in 2011, Luis von Ahn and his student, Severin Hacker, founded Duolingo.

Duolingo up 4 million users after Apple endorsement

Von Ahn had sold his company (reCAPTCHA) to Google and wanted to work on an education-related project. He saw how difficult it was for the people in his community in Guatemala to learn English. At the same time, he was aware of the benefits of speaking English and the opportunities it offers.

Fun fact: The Duo mascot is a green owl because the co-founder, Severin Hacker, hates the color green.

In October 2011, the company raised $3.3 million led by Union Square Ventures, with participation from author Tim Ferriss and actor Ashton Kutcher.

It launched a private beta on November 30th, 2011, and within 2 weeks, had a waiting list of more than 100,000 people.

It was launched on June 19th, 2012, and by then, the watchlist had grown to around 500,000.

By July 2013, there were 5 million users.

By July 2017, there were over 200 million registered users.

One year later, there were 300 million registered users.

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