AI と人間の講師を組み合わせることで学習を個別最適化するプレプリの取り組み

Preply⁠(opens in a new window) is the world's largest marketplace for online language learning, connecting more than 100,000 expert tutors with learners across more than 180 countries. Through personalized one-to-one instruction across more than 90 languages, Preply’s mission is to make high-quality language education accessible to anyone, anywhere.

Language learning is fundamentally human. It requires conversation, confidence, motivation and cultural understanding. While Preply tutors provide irreplaceable energy, motivation, cultural nuance, and human connection for learners, they also face repetitive tasks: writing personalized plans and lesson notes. Students, meanwhile, often require a clear sense of progress to keep engagement high.

Preply saw an opportunity to use AI to strengthen—not replace—the relationship between tutors and learners. The result was Lesson Insights, an OpenAI API-powered experience that transforms every lesson into a personalized learning journey.

After each 1:1 lesson, OpenAI analyzes the lesson transcript and generates tailored feedback across grammar, vocabulary, and pronunciation. Learners receive actionable guidance. Tutors spend less time on administrative work. And both gain a richer understanding of progress over time.

“I think the biggest opportunity in language learning is in personalization. There are so many elements specific to individual humans that are hard, if not impossible, to be captured by humans. AI can do it much better.”

—Dmytro Voloshyn, Co-founder & CTO, Preply

Building AI around human teaching

To find the right technology partner, Preply evaluated multiple AI models across language-learning tasks. OpenAI consistently delivered strong performance, while providing the speed, reliability, and production readiness needed to serve learners at global scale.

“We decided to partner with OpenAI because it provides state-of-the-art models for us, which solve problems for our customers,” says Dmytro Voloshyn, Co-founder & CTO, Preply. “It’s now at the center of our ecosystem and how we operate as a company.”

Preply introduced ChatGPT Enterprise across its organization, running company-wide enablement sessions for more than 600 employees across New York, Kyiv, London and Barcelona. Weekly active usage quickly grew from 60% to 95%, helping embed AI into everyday work across teams.

Turning every lesson into a personalized learning journey

Lesson Insights became the centerpiece of Preply's customer-facing AI strategy. Lessons take place in the Preply Classroom, and with learner consent, the sessions are recorded and transcribed. Insight generation is scheduled a few minutes before the end of the session, so feedback is ready for the tutor and student to review together.

Within minutes of a lesson ending, the learner and their tutor receive a structured, personalized report in their chat thread that includes:

• A summary of key lesson topics
• Grammar corrections and explanations
• Vocabulary highlights and translations
• Pronunciation feedback
• Recommended next steps

Those insights feed directly into Preply’s self-learning exercise engine to generate personalized homework—turning every human lesson into structured practice that compounds over time.

“We were hearing time and time again, ‘How am I doing? Am I getting better? What do I get to do next?,’” says Emily Stott, Staff Product Manager at Preply. “Students wanted a more tangible view of their growth. Now, with Lesson Insights, we're able to understand exactly what you've been talking about, your goals, the topics you've been covering, your tutor’s feedback, and convert that into highly personalized and targeted practice.”

The result is a continuous learning experience that extends far beyond the lesson itself, helping learners build confidence, stay motivated, and make real progress. Instead of treating each session as a standalone event, learners receive guidance that compounds over time—creating a clearer path toward fluency.

Transforming how Preply operates internally

Today, Preply uses OpenAI APIs across the organization, supporting customer service workflows, connecting internal systems, and helping teams automate operational processes. Custom GPTs, like its Brand Voice GPT, are embedded into daily workflows, helping teams create content that stays consistent with Preply’s tone, messaging, and brand standards.

The company has also embraced Codex as a core part of its engineering workflow.

“It's the topic I'm most excited about,” says Dmytro. “Codex helps us write code with a speed that was previously unseen. With such a powerful tool, engineers can focus more on architecture in the system as a whole and solving customers' problems.”

Around 94% of Preply engineers use Codex and AI coding assistants for code generation, PR reviews, debugging, and accelerating development workflows. By reducing time spent on routine coding tasks, engineering teams can focus on building new learning experiences, scaling products across languages, and delivering value to tutors and learners faster.

For Preply, AI is no longer a standalone initiative—it's becoming part of how the company builds products, serves customers, and operates day to day.

“There is an amazing opportunity for Preply to combine what humans are the best at—motivation, engagement, energy—with AI as a copilot. AI can handle all of the repetitive and administrative tasks.”

—Dmytro Voloshyn, Co-founder & CTO, Preply

Results at a glance

Preply has always had very high engagement on a per lesson basis. But its AI-generated summaries are helping students become even more motivated. The company reports that most active learners still engage with Lesson Insights more than a year later—with both tutors and students providing strong product feedback—boosting overall retention.

“We know AI-powered tools might have an element of novelty,” says Emily. “But if people are coming back and engaging months later, time and time again, that’s a very strong signal of value—learners and tutors find value in our solutions.”

Results:

• 95% ChatGPT weekly active usage among Preply employees
• 75% of English-language learners actively use Lesson Insights, powered by OpenAI APIs
• More than 70% of tutors use the feature
• Around 75% of active learners continue engaging with Lesson Insights more than a year after adoption
• 4.7/5 satisfaction rating among tutors and students, from more than 300k ratings received directly on the platform
• 70% product market fit score, significantly above the threshold often associated with strong customer demand

AI as a force for good

For tutors like Michelle Garcia Ramos, AI has become a practical teaching assistant—one that helps reduce preparation time while improving the learning experience.

Before Lesson Insights, creating personalized homework assignments and lesson materials could take hours. Now, much of that work happens automatically, allowing tutors to focus on supporting students directly.

“Before I started using Preply's AI feature, I would spend hours and hours prepping for classes and creating homework. But now that time has been cut by more than half.”

—Michelle Garcia Ramos, Spanish tutor, Preply

For Michelle, the benefit isn't simply efficiency. AI provides ideas, highlights learning opportunities, and helps identify what students should focus on next.

The result is better preparation, more focused lessons, and faster progress for learners.

Leadership lessons

• Treat AI as a cultural transformation, not a tooling rollout: Adoption accelerates when leadership sets a clear strategy, teams are trained to use it, and AI becomes part of everyday work across the business
• Pick high-impact use cases: It’s better to go deep on a small number of features with clear user value and measurable impact than many experiments that don’t reach quality
• Build partnerships: Work with organizations that can support rollout, develop teams’ knowledge, and collaborate on how to solve customers’ problems in the best way

“It's not about replacing humans. It's about augmenting them with new capabilities and also sometimes redefining the essence of the job.”

—Dmytro Voloshyn, Co-founder & CTO, Preply

Tips

• Make it a company priority: Preply’s adoption of ChatGPT Enterprise was reflected in its strategy, roadmaps, and objectives—signaling that its use was an expectation, not an experiment
• Invest in enablement: Structured training, hands-on workshops, and internal sessions helped teams move from curiosity to practical usage
• Work with users: Preply collaborated with tutors to build data sets, evaluate prompts and ensure it had high standards for quality

What’s next

For Preply, the future of language learning is increasingly personalized.

The company plans to build on Lesson Insights with experiences that create a deeper understanding of every learner over time—capturing goals, progress, strengths, challenges, and learning preferences across months of study.

The vision is a learning experience that adapts continuously around each individual, providing more precise guidance, pacing, curriculum recommendations, and feedback.

“We're only at the beginning,” says Emily. “AI will make language learning dramatically more personalized: every learner will have a clear picture of exactly where they started, where they are now, and what they need to work on next. Not a one-size-fits-all curriculum, but a learning experience that adapts around each individual.”

AI is also transforming how Preply builds products internally. As agentic development tools become increasingly capable, more employees can participate in building solutions—not just consuming them. That means faster innovation, broader experimentation, and greater support for learners and tutors around the world.

For Dmytro, the opportunity remains clear: combine the strengths of human teachers with the power of AI.

“OpenAI as a partner was able to teach us how to use the product in the most efficient way. And who can teach you better than the organization that created the best large language models in the world.”

—Dmytro Voloshyn, Co-founder & CTO, Preply

The future, Preply believes, isn't human or AI. It's human-led, AI-enabled.