Disclaimer – This critique is intended for discussion and analysis purposes only and is not intended to discredit the efforts of Duolingo or its users.

Duolingo has become one of the most popular methods for learning a language in the world since it was founded in 2011 – its fun and accessible layout makes it a great option for beginners to gain a basic knowledge of a new language. However, Duolingo is not without its flaws, and these flaws have arguably been playing a role in the decline of linguistic diversity across the globe.

As of 2025, there are 7, 110 known languages in the world, and this number is already in decline – Duolingo currently offers only approximately 0.6% of the world’s languages. That is, there are 43 languages available to learn, 2 of which are from works of fiction. A stark number of important languages are missing, including the official languages of countries including Belarus, Thailand, and Bangladesh, to name just a few of many. The small number of languages available on Duolingo draws attention to a much larger problem regarding attitudes towards language learning in the West, which has a ripple effect for the international linguistic mosaic.

The fact that there are 2 languages from fictional works (‘Klingon’ from Star Trek, and High Valyrian from A Song of Fire and Ice/Game of Thrones) arguably implies that there are languages in the world that are not as worthy of attention in the West. Instead, these ‘fictional’ languages are prioritised, which has detrimental effects on those languages that are not as commonly spoken or learnt, particularly those that are at risk of extinction, or ‘linguicide’. That Duolingo offers fictional languages at the expense of other historic and culturally significant languages is certainly controversial – although these fictional languages may be fun to use in social situations, other languages should also be worthy of attention and indeed protection. There does not seem to be much information regarding other language courses that are currently in development. Duolingo clearly has a long way to go when it comes to improving its educational resources for a diverse range of languages, particularly those that are at risk of extinction.

The limited number of languages offered by Duolingo perhaps signifies another problem regarding language learning in the West – languages are often learnt for a purpose and are seemingly judged based on their use. Of course, this is not always the case, as many may choose to learn a language to connect with their heritage or to expand their cultural knowledge. However, it does seem fair to suggest that languages are sometimes judged based on their merit, particularly with regard to employment competition as candidates may improve their credentials and employability by learning a language. It seems that there are certain languages that are more desirable to employers, meaning that they are more likely to receive attention from companies such as Duolingo. The problem is not the fact that these languages are prioritised for their utility, but rather that other languages are neglected because they are not deemed ‘useful’. Each language has its own merit, and each language is worthy of recognition – it is time for Duolingo to honour this. 

It is plausible that Duolingo is playing a role in the extinction of languages – by focusing on those that are most popular or desirable, other important languages have become disregarded or even forgotten. That is not to say that Duolingo should suddenly offer every single language in the world, but rather that it ought to demonstrate promising signs of progress with regard to its catalogue of languages. Sadly, Duolingo has closed its ‘Incubator’ website as the company was profiting from the hard work of volunteers, which violated IPO regulations. This allowed volunteers to contribute to the development and implementation of new language learning resources, but there is no longer an official platform to view the progress of new language courses. Duolingo’s global popularity also comes with some level of responsibility, and perhaps it needs to take a more active role concerning the protection of at-risk languages.

Duolingo has over 110 million users per month and is frequently reviewed as one of, if not the best app for learning a language. Of course, Duolingo does have its assets – its layout is visually appealing, and it certainly encourages new learners with its friendly (if somewhat overactive) mascot Duo. However, given its reputation, it seems fair to propose that Duolingo ought to take more responsibility with regard to the problem of language extinction.

Written by Natasha, a third year International Relations student at UoL/LSE based in the UK.