The Pittsburgh-based company is one of many — including , , , and — that provide instruction for children and adults. But the language phenom hopes its broader popularity will help it gain traction in a complex space.

“Duolingo certainly arrives late to the party, but their brand recognition, UX design expertise and enormous user base give them a unique advantage,” said Paul Darvasi, CEO and co-founder of , a Montreal-based company with more than 15 years of experience creating learning games. “Personally, I feel math is often taught out of context. Students learn formulas and procedures, but as they get older they rarely know how they will be applied. I believe games and simulations will be able to better connect math to the real world.”

Duolingo, the language learning app in the world, won’t disclose the exact number of users for its math offering, launched in August 2022, but company spokeswoman Monica Earle said it’s in the millions. She said, too, the application’s creators hope it will help alleviate math anxiety, a common phenomenon among children and adults. 

Duolingo’s current math offerings span third grade through early middle school. Samantha Siegel, a company software engineer who spearheaded the math course’s development, said it started with third graders because of the critical lessons taught at that level.

“If you don’t understand how fractions work, it can predict your math performance and proficiency for the rest of your education career,” Siegel said.

She said the company uses real-world problems to further students’ comprehension of what might otherwise seem like abstract concepts.

“We do a lot with implicit learning … you learn by doing,” she said. “We have developed a really proven and unique way of approaching education and packaging it in a really fun way. Why shouldn’t we be the one to apply this to other subjects?”

American students have struggled with mathematics for decades. The Common Core, a controversial set of academic standards rolled out in 2010, was meant to correct the unevenness in how the subject was taught across the nation and deepen students’ understanding. It was met with sharp disdain from teachers, parents and students. 

Despite the derision, it became a symbol of academic rigor and continue to use Common Core math. But even with the new standards, American students continued to flail: Test scores persistently lagged for most, though have emerged in recent months.

A 2024 Urban Institute only reinforced the subject’s importance. It found that increasing math scores helps deliver stronger long-term returns for students — especially related to earnings — compared to reading. 

What’s less obvious, at least to some, is the value of game-based approaches to learning this challenging subject. Critics worry about what they say is Duolingo’s skin-deep approach. 

Keith Devlin, a mathematician and Stanford University professor emeritus, knows repetitive practice is valuable in learning almost anything and that video games and interactive software in general are excellent at keeping people engaged. He’s not as confident, however, in the idea that these applications will create mathematical thinkers.

“The real question is, do games produce better ability to solve a mathematical problem that is more than a basic skill? For the majority of games, the answer is no,” he said. “They often do result in students having a more positive attitude to math — and that’s a plus.”

But they don’t teach users how to solve math problems that require a train of thought, he said. 

“Where they can fall short is in the tendency to focus too heavily on rote practice or gamified repetition without enough conceptual depth,” Gold Bug Interactive’s Darvasi said. “Math understanding requires more than speed and accuracy; it needs problem-solving, reasoning and connections to real-world contexts. Apps that fail to integrate those richer experiences risk reinforcing procedural knowledge without deep comprehension.”

Darvasi said, too, that digital math learning can become isolating if it isn’t paired with collaborative, discussion-based problem-solving — like the kind found in traditional classrooms.

“However, these are temporary setbacks,” he said in assessing current online offerings from multiple companies. “With the latest tools in adaptive learning, thoughtful game design, and technology that can generate fresh challenges on the fly, the path is opening for math to be taught in ways that are engaging, meaningful, and tailored to the learner.”

Duolingo Math’s target audience, spokeswoman Earle said, is students who struggle with the subject and those who enjoy it enough to do it for fun. Cartoon figures and colorful graphics help guide users through the math problems, offering encouragement along the way. 

Roughly 90% of users access Duolingo, which also runs programs off its website, for free. Others pay either $12.99 a month or $95.99 a year for Super Duolingo, which avoids ads and allows for unlimited practice. A second level, Duolingo Max, costs $29.99 a month or $167.99 a year and offers enhanced, generative-AI-powered conversation features. 

Despite some about the limitations of the language learning tool and a recent kerfuffle over how much AI would shape the product, Duolingo’s reported for 2025 were $252.3 million, up from $178.3 million a year ago.

Nicole Paxton, principal of Mountain Vista Community School in Colorado Springs, said her school relies upon Math Catalyst, a teacher-led, concept-focused program from . It is not a computer-based game, but “a structured set of mini-lessons and practice activities that target specific learning gaps and build strong mathematical reasoning”, she said. 

“If used as a supplement at home, a program like Duolingo Math could be helpful for fluency and fact practice, but it would not replace the intentional, standards-based support students receive through Math Catalyst,” Paxton said. 

Earle said the program also allows for personalization using machine learning to tailor each lesson. Once it identifies a weakness in students’ understanding, it will present them with these same problems until they can solve them. 

But the main purpose of the venture, software engineer Siegel said, is to make math feel fun.

“Duolingo is really delightful,” she said. “That’s our bread and butter.”

That’s a question Duolingo is grappling with this spring after an published in April to the job posting site LinkedIn revealed that the Pittsburgh-based company will become “AI-first,” largely doing away with the human contractors who develop courses. In the meantime, it’ll focus on using AI to run basic functions of its app, such as a new chatbot that engages users in live conversations in hundreds of languages. 

It’s perhaps the most extensive shift into AI to date for an education provider, representing a huge bet on the reliability of large language models that publicly debuted less than three years ago — and which remain notorious for .

Founded in 2011 at Carnegie Mellon University, Duolingo is now worth . Last year it boasted more than monthly active users. Its largest U.S. user group is under 18, but users span all ages. In 2016, Duolingo launched a free app .

Developers needed 12 years to develop the first 100 courses for its massively popular mobile phone app, known by its ubiquitous . Using AI, they created in just the past year, founder and CEO Luis von Ahn said in the email. Just as developing a mobile app in 2012 helped the company grow exponentially, he predicted the shift toward AI will prove equally significant.

“To teach well, we need to create a massive amount of content, and doing that manually doesn’t scale,” von Ahn said in the email. Expanding without AI would take decades. “We owe it to our learners to get them this content ASAP.”

To do so, Duolingo will gradually stop using human contractors “to do work that AI can handle.”

While turning to AI may well accelerate course development, the move is angering veteran users who predict that replacing humans with bots will weaken the app with inaccurate, lower-quality content. In protest, many have threatened to delete it from their phones.

On Blue Sky, one user , “Just dropped a 1 star review, f*** Duolingo for doing this.”

On X, a user wrote simply, “Duo joins the dark side.”

Duolingo did not immediately respond to a request from The 74 for comment. In a May 2 with Bloomberg News, von Ahn attributed the blowup among users to a “misunderstanding,” but his explanation for the move confirmed that the company will largely replace human course developers with AI, as users fear. 

“What we said is that whenever there is some job that can be done by AI, and it can be done really well, then we’re unlikely to hire contractors to do that job,” he said.

The announced policy won’t affect full-time employees, he said. 

Duolingo employs about 900 people and continues to grow as the company adds offerings in math, music and other subjects, , Duolingo’s vice president of learning, noted recently. 

But AI is forcing the company to ask essential questions, she said during a talk at the 2025 in April. “We’re going to continue hiring people, but we’re going to be a little bit more intentional-thinking about what roles really are going to impact our business.”

So the company will focus on “people who are very versatile” and who are comfortable and “excited” about AI, she said.

Cem Kansu, Duolingo’s head of product, last November that AI has been “transformational,” helping the company quickly create new content and build interactive features.

“The whole machine of content creation at Duolingo has gained insane speed in the past two years.”

‘Guess I’ll find different ways to learn’

In a last month with the tech podcast No Priors, von Ahn said Duolingo originally created a lot of content “half by hand, half automatically,” making for a slow process.

AI, von Ahn said in the April memo, would help employees “focus on creative work and real problems, not repetitive tasks.”

The explanation may be too little too late for many users, who said the move to largely get rid of contractors who create courses was prompting them to stop using Duolingo, in many cases sacrificing valuable “streaks” of hundreds or thousands of consecutive days spent using the app. 

One , “Well I just ended my family plan subscription & killed my 530 day streak. Guess I’ll find different ways to learn.” He added a waving hand emoji.

Another , “In my opinion it is now complete rubbish — I have let go of my nearly 900 day streak and unsubscribed — bring back humans.”

The company its contractor workforce in January using AI, when it “offboarded” 10% of them, a company spokesman told Bloomberg. “We just no longer need as many people to do the type of work some of these contractors were doing.”

, an AI education specialist and language course designer based in Spain, said language teachers may rightly worry about the loss of nuance when AI is generating lessons. “Language isn’t only structure — it’s emotion, culture and tone,” she wrote in a letter to her students that she shared with The 74. “AI doesn’t always grasp that.”

But the move, Lucchesi said, offers a clear boost for access: “A student in rural India can now learn English with support in Hindi, without waiting for a local instructor or textbook.” 

And while the benefits to “endless conversation practice” and pronunciation feedback are clear, she said, that may only go so far. “Learning a language is social, emotional, and cultural. Motivation often comes from connection — a teacher who encourages you, a classmate who laughs with you, a shared context that makes words meaningful. AI can support that, but it can’t replace it.”

Benjamin Riley, a well-known AI-in-education skeptic, said it makes sense that generative AI would be incorporated by a language app, since Google engineers developed the breakthrough technology underlying it, known as , while working on translating human language.

“It’s a natural fit,” he said. “But the bigger question might be this: In a world where AI might — emphasis on might — be able to simultaneously translate between any two human languages, why would people bother to become bilingual at all?”

He invoked the science-fiction fantasy of the , a universal translator featured in The Hitchhiker’s Guide to the Galaxy, which now seems “within reach,” he said, given current AI developments.

“The optimist might see this as reducing cross-cultural friction because we can all talk to one another. The pessimist might worry about languages dying because they aren’t prevalent enough to be fed into AI training models, and that something important will be lost if humans are monolingual.”

Kansu, Duolingo’s head of product, said he’s not worried about AI making language learning obsolete, since even with the best translation service, workers must still wait for it to process speaking. “Would you want to work with someone that has a 15-second lag in every interaction? I don’t think humans want that today.”

Chatting with Lily

At the ASU+GSV summit, Pajak, Duolingo’s vice president of learning, told an interviewer that large language models, or LLMs, made possible a new feature that allows users to converse in many languages with a . “I’m very excited about it. I use it almost every day to practice my Italian,” she said.

A former language teacher, Pajak said that back-and-forth is key to learning a language. “You want to actually be able to speak” to improve. 

User enthusiasm for the chats with Lily helped drive a 50% rise in subscriptions, the company said recently, noting that the bot is included in Duolingo’s most expensive tier.

, a nonresident senior fellow at the conservative American Enterprise Institute who specializes in AI, said Duolingo’s move seems smart. “Leaning into ‘AI-first’ is just an acknowledgement that these capabilities are only going to get better and cheaper over time,” he said.

In the interview last month, von Ahn predicted that education systems will change over the next few years to offer better, more reliable feedback to students. AI, he said, will scale good teaching.

“There are extremely good teachers for sure, but there’s not very many of them — and certainly most everybody in the world doesn’t have access to a good one.”