Roblox: Breaking Down Language Barriers with a Multilingual Translation Model February 5, 2024

Imagine discovering that your new Roblox friend, a person you’ve been chatting and joking with in a new experience, is actually in Korea — and has been typing in Korean the entire time, while you’ve been typing in English, without either of you noticing. Thanks to our new real-time AI chat translations, we’ve made possible on Roblox something that isn’t even possible in the physical world — enabling people who speak different languages to communicate seamlessly with one another in our immersive 3D experiences. This is possible because of our custom multilingual model, which now enables direct translation between any combination of the 16 languages we currently support (these 15 languages, as well as English).

In any experience that has enabled our in-experience text chat service, people from different countries can now be understood by people who don’t speak their language. The chat window will automatically show Korean translated into English, or Turkish translated into German, and vice versa, so that each person sees the conversation in their own tongue. These translations are displayed in real time, with latency of approximately 100 milliseconds, so the translation happening behind the scenes is nearly invisible. Using AI to automate real-time translations in text chat removes language barriers and brings more people together, no matter where they live in the world.

Roblox: Building a Unified Translation Model

AI translation is not new, the majority of our in-experience content is already automatically translated. We wanted to go beyond translating static content in experiences. We wanted to automatically translate interactions — and we wanted to do that for all 16 languages we support on the platform. This was an audacious goal for two reasons: First, we weren’t just translating from one primary language (i.e., English) to another, we wanted a system capable of translating between any combination of the 16 languages we support. Second, it had to be fast. Fast enough to support real chat conversations, which to us meant getting latency down to approximately 100 milliseconds.

Roblox is home to more than 70 million daily active users all over the world and growing. People are communicating and creating on our platform — each in their native language — 24 hours a day. Manually translating every conversation happening across more than 15 million active experiences, all in real time, is obviously not feasible. Scaling these live translations to millions of people, all having different conversations in different experiences simultaneously, requires an LLM with tremendous speed and accuracy. We need a context-aware model that recognizes Roblox-specific language, including slang and abbreviations (think obby, afk, or lol). Beyond all of that, our model needs to support any combination of the 16 languages Roblox currently supports.

To achieve this, we could have built out a unique model for each language pair (i.e., Japanese and Spanish), but that would have required 16×16, or 256 different models. Instead, we built a unified, transformer-based translation LLM to handle all language pairs in a single model. This is like having multiple translation apps, each specializing in a group of similar languages, all available with a single interface. Given a source sentence and target language, we can activate the relevant “expert” to generate the translations. Read More

Continuously Improving Accuracy

In testing, we’ve seen that this new translation system drives stronger engagement and session quality for the people on our platform. Based on our own metric, our model outperforms commercial translation APIs on Roblox content, indicating that we’ve successfully optimized for how people communicate on Roblox. We’re excited to see how this improves the experience for people on the platform, making it possible for them to play games, shop, collaborate, or just catch up with friends who speak a different language.

The ability for people to have seamless, natural conversations in their native languages brings us closer to our goal of connecting a billion people with optimism and civility.

To further improve the accuracy of our translations and to provide our model with better training data, we plan to roll out a tool to allow people on the platform to provide feedback on their translations and help the system improve even faster. This would enable someone to tell us when they see something that’s been mistranslated and even suggest a better translation we can add into the training data to further improve the model.

These translations are available today for all 16 languages we support — but we are far from done. We plan to continue to update our models with the latest translation examples from within our experiences as well as popular chat phrases and the latest slang phrases in every language we support. In addition, this architecture will make it possible to train the model on new languages with relatively low effort, as sufficient training data becomes available for those languages. Further out, we’re exploring ways to automatically translate everything in multiple dimensions: text on images, textures, 3D models, etc.

And we are already exploring exciting new frontiers, including automatic voice chat translations. Imagine a French speaker on Roblox being able to voice chat with someone who only speaks Russian. Both could speak to and understand one another, right down to the tone, rhythm, and emotion of their voice, in their own language, and at low latency. While this may sound like science fiction today, and it will take some time to achieve, we will continue to push forward on translation. In the not-too-distant future, Roblox will be a place where people from all around the world can seamlessly and effortlessly communicate not just via text chat, but in every possible modality!