Here's a story about how two college dropouts decided that the best way to learn a language isn't memorizing verb conjugations—it's actually speaking. Wild concept, right?

Speak, an AI-powered language tutoring platform, just crossed $100 million in annualized revenue while hitting a $1 billion valuation, according to Forbes. The startup was built by two Thiel Fellowship alumni who figured out that people desperately want to learn languages but hate the way most apps teach them. Instead of drilling grammar rules, Speak throws you into voice-based conversations where you order coffee, ask for directions, or chat with classmates. You know, the stuff you'd actually do if you traveled somewhere.

From Seoul to Everywhere

Co-founder Connor Zwick launched Speak in Seoul after noticing something obvious: South Koreans were obsessed with learning English, but traditional education was failing them spectacularly. Students memorized grammar patterns but couldn't hold a basic conversation.

"English language learning there was like an obsession," Zwick said. "There was such latent demand."

So Speak took a different approach. The platform runs on OpenAI technology and uses voice-based scenarios to simulate real-world situations. Users can create custom practice scenes through simple prompts, and the app includes streak tracking and leaderboards to keep people coming back. It's part language tutor, part video game incentive structure.

The app now offers lessons in six languages: English, Korean, Spanish, Japanese, French, and Italian. Since launch, it's racked up roughly 15 million downloads. The business model starts with free access, then converts users to paid tiers ranging from $80 to $200 for more advanced content. Most revenue comes from these consumer subscriptions.

Taking on the Big Player

In 2024, Speak added enterprise training after individual users started asking if their employers could pay for it. Now roughly 500 companies, including KPMG and HD Hyundai, offer Speak accounts to employees in South Korea. The platform expanded into Japan and Taiwan before entering the U.S. market in June.

Speak has raised $160 million from investors including Khosla Ventures, Accel, and the OpenAI Startup Fund. That's impressive, but let's talk about the elephant in the room: Duolingo (DUOL) generated $724 million in revenue last year and is targeting $1.02 billion by year-end. The gap is enormous.

Duolingo recently launched AI-driven video sessions with its mascot character Lily, signaling that it's also betting heavily on automated tutoring. But Zwick argues that Speak's philosophy is fundamentally different. Duolingo emphasizes vocabulary building and structured grammar rules. Speak prioritizes spoken comfort and pronunciation through active dialogue.

Zwick said users engage in spoken practice far more frequently on his platform compared to other language apps. He characterized mobile game-style learning tools as "guilt-free phone time," adding that his product aims for a more serious learning experience. Translation: other apps gamify language learning so you feel productive while scrolling. Speak wants you to actually learn.

The Thiel Fellowship Connection

Zwick and co-founder Andrew Hsu met through the Thiel Fellowship in 2012. Zwick left Harvard to build Flashcards+, a study tool that eventually got acquired by education company Chegg (CHGG). Hsu dropped out of a Stanford Ph.D. program a year earlier to join the fellowship.

Both spent time learning machine learning fundamentals by auditing classes at UC Berkeley and Stanford without formal enrollment. Those sessions included lectures taught by John Schulman, who would go on to co-found OpenAI. So they were literally learning AI from the people who would later build the technology powering their product.

Khosla Ventures Partner and Managing Director Sven Strohband told Forbes he evaluated early versions of the app back in 2017. Even then, before Speak introduced full conversational features, the software could recognize foreign accents with impressive accuracy. He described the founders as early adopters of an AI-first approach, which makes sense given their background.

As OpenAI's models continue improving, so does Speak. The platform now includes accent guidance and dynamic lesson adjustments—features that weren't technically possible during its early development. The product essentially gets better as the underlying AI technology advances, which is a nice position to be in.

The Road Ahead

Speak is growing fast, but catching Duolingo won't be easy. The revenue gap is massive, and Duolingo has years of brand recognition and a massive user base. But Speak is carving out its own niche by focusing on speaking practice over gamified lessons.

The real question is whether enough people want to actually speak a new language versus just feel productive while playing with an app on their commute. If Speak is right about that distinction, they might have a real shot at building something significant. And at a $1 billion valuation with $100 million in revenue, they're already well on their way.